The final volume of the balloon is 0.61 L
The Ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation to the behaviour of many gases under many conditions, although it has several limitations. The ideal gas equation can be written as-
PV = nRT
where,
P = Pressure
V = Volume
T = Temperature
n = number of moles
Given,
Initial volume = 0.55 L
Initial Pressure = 1 atm
Final pressure = 0.9 atm
P₁V₁ = P₂V₂
1 × 0.55 = 0.9 × V₂
V₂ = 0.61 L
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how would the rf values change if a more polar solvent were used
When a more polar solvent is used in TLC, the more polar compounds will travel further up the TLC plate than the less polar compounds.
Retention factor (Rf) is a measure of the distance a compound travels in a thin layer chromatography (TLC) experiment relative to the distance the solvent travels.
Polarity is a measure of how strongly a molecule interacts with other molecules.
Solvent polarity is a measure of how strongly a solvent interacts with other molecules.
. This is because the more polar compounds will interact more strongly with the more polar solvent. As a result, the Rf values of the more polar compounds will increase.
For example, if a mixture of compounds containing both polar and non-polar compounds is analyzed using a TLC plate developed with a non-polar solvent, the polar compounds will travel shorter distances than the non-polar compounds. However, if a more polar solvent is used, the polar compounds will travel further up the TLC plate and their Rf values will increase.
The Rf values of the compounds can be used to identify the compounds in the mixture. A reference standard of each compound can be run on the same TLC plate under the same conditions to compare the Rf values. The compound with the same Rf value as the reference standard is the same compound.
TLC is a quick and easy method for separating and identifying compounds in a mixture. The Rf values can be used to identify the compounds in the mixture and the polarity of the solvent can be used to control the separation of the compounds.
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How many compounds with the formula C4H11N contain a 2° amine and a single 2° carbon atom? 0 1 2 3 4 ( answer is 1)
There is only one compound with the formula C₄H₁₁N that contains a secondary amine and a single secondary carbon atom. (Option b.)
To determine the number of compounds with the formula C₄H₁₁N that contain a secondary amine (2° amine) and a single secondary carbon atom, we need to consider the possible structural arrangements.
A secondary amine (2° amine) has the general structure R₂NH, where R represents an alkyl or aryl group. In the case of C₄H₁₁N, we have four carbon atoms and one nitrogen atom.
To have a single secondary carbon atom, we need one of the carbon atoms in the compound to be directly bonded to the nitrogen atom. Additionally, the remaining three carbon atoms must be bonded to the other carbon atoms or hydrogen atoms.
Let's examine the possibilities:
The secondary amine group is attached to the primary carbon atom (1° carbon): In this case, we have a primary amine rather than a secondary amine. Therefore, this arrangement is not valid.
The secondary amine group is attached to one of the terminal carbon atoms (3° carbon): In this case, we have a tertiary amine rather than a secondary amine. Therefore, this arrangement is not valid.
The secondary amine group is attached to one of the two adjacent carbon atoms (2° carbon): This arrangement fulfills the criteria of having a secondary amine and a single secondary carbon atom.
Therefore, there is only one compound with the formula C₄H₁₁N that contains a secondary amine and a single secondary carbon atom.
The correct answer is (b) 1.
The correct question is:
How many compounds with the formula C₄H₁₁N contain a 2° amine and a single 2° carbon atom?
a. 0
b. 1
c. 2
d. 3
e. 4
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25) Calculate the molar solubility of thallium chloride in 0.40 M NaCI at 25°C. Ksp for TICI is 1.7× 10-4, A) 6.8 x 10-5 M B) 4.2 x 10-4 M C) 8.2× 10-3 M D) 1.3 x 10-2 M
The molar solubility of thallium chloride in 0.40 M NaCI at 25°C can be calculated using the Ksp expression is option A, [tex]6.8 * 10^{-5}[/tex] M.
Molar solubility is the molarity of a solute in a saturated solution at a certain temperature. In other words, molar solubility refers to the maximum concentration of a solute that can be dissolved in a solvent at a particular temperature until the solution becomes saturated.
Ksp (solubility product constant) is a chemical constant used to determine the solubility of an ionic compound. It is the equilibrium constant for the dissociation of a solid substance into ions. Ksp varies with temperature and pressure. It can be determined from the concentrations of the dissolved ions or from the solubility of the compound.
The equation for the dissociation of thallium chloride in water is: [tex]TICI (s) = T^{+} (aq) + CI^{-} (aq)[/tex]
The Ksp expression for thallium chloride is: [tex]Ksp = [T^{+}][CI^{-}][/tex].
The solubility of thallium chloride in 0.40 M NaCI is assumed to be x M. Because NaCI is a common ion, the equilibrium expression for the dissociation of thallium chloride is written as: [tex]TICI (s) = T^{+} (aq) + CI^{-} (aq)+ NaCI (aq)[/tex].
TICI dissociates in water to produce [tex]T^{+}[/tex] and [tex]Cl^{-}[/tex] ions. These ions then combine with Na+ and CI- ions from NaCI, respectively, to form TCI and Na+. Because NaCI is a strong electrolyte, the concentration of Na+ and CI- ions produced from NaCI is unaffected by the dissociation of TICI.
Therefore, the concentration of [tex]T^{+}[/tex] ions and [tex]Cl^{-}[/tex] ions in the saturated solution are given as follows: [tex][T^{+}] = xM[CI^{-}] = xM[/tex].
Substituting these values in the Ksp expression gives: [tex]Ksp = [T^{+}][CI^{-}]= (x)(x)= x^{2}[/tex]
The value of Ksp for TICI is [tex]1.7* 10^{-4}[/tex]. Substituting this value in the expression:
[tex]x^{2} = Kspx = \sqrt{Kspx} = \sqrt{(1.7* 10-4)x} = 4.12* 10^{-3} M[/tex]
However, this concentration corresponds to the solubility of TICI in pure water. In 0.40 M NaCI, the concentration of CI- ions is not negligible, and hence, it needs to be considered.
Because TICI dissociates to produce one T+ ion and one CI- ion, the concentration of CI- ions in the solution is:
x = [[tex]Cl^{-}[/tex]]Therefore, the concentration of CI- ions in the solution is 0.4 + x M.
Finally, the concentration of CI- ions in the solution is substituted in the expression for [CI-] to give:
[tex]x^{2} = Ksp/[CI^{-}]x = \sqrt{(Ksp/[CI^{-}]} = \sqrt{\frac{1.7*10^{-4}}{0.4}}= 6.8 * 10^{-5} M[/tex]
The molar solubility of thallium chloride in 0.40 M NaCI at 25°C is [tex]6.8 * 10^{-5}[/tex] M. Therefore, the correct answer is option A.
The molar solubility of thallium chloride in 0.40 M NaCI at 25°C is [tex]6.8 * 10^{-5}[/tex] M.
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how many moles of so2 contain 8.02 × 10^21 atoms of oxygen?
To determine the number of moles of SO2 that contain 8.02 × 10^21 atoms of oxygen, we need to consider the molar ratio between oxygen atoms and SO2 molecules. Based on the molecular formula of SO2, we can calculate the number of moles using Avogadro's number and the given number of atoms of oxygen.
The molecular formula of sulfur dioxide (SO2) indicates that it contains one sulfur atom (S) and two oxygen atoms (O). To find the number of moles of SO2 corresponding to 8.02 × 10^21 atoms of oxygen, we first calculate the number of moles of oxygen atoms.
Given: Number of oxygen atoms = 8.02 × 10^21 atoms
Using Avogadro's number (6.022 × 10^23 atoms/mol), we can convert the number of oxygen atoms to moles:
Number of moles of oxygen = (8.02 × 10^21 atoms) / (6.022 × 10^23 atoms/mol) ≈ 0.0133 mol
Since there are two oxygen atoms in one SO2 molecule, the number of moles of SO2 would be half of the number of moles of oxygen:
Number of moles of SO2 = 0.0133 mol / 2 = 0.00665 mol
Therefore, approximately 0.00665 moles of SO2 contain 8.02 × 10^21 atoms of oxygen.
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Using Avogadro's number, 0.00665 moles of [tex]SO_2[/tex] contain atoms of [tex]8.02 * 10^{21}[/tex]oxygen.
To determine the number of moles of SO2 that contain [tex]8.02 * 10^{21}[/tex] atoms of oxygen, we need to consider the molar ratio between oxygen atoms and [tex]SO_2[/tex] molecules. Based on the molecular formula of [tex]SO_2[/tex], we can calculate the number of moles using Avogadro's number and the given number of atoms of oxygen.
The molecular formula of sulfur dioxide ([tex]SO_2[/tex]) indicates that it contains one sulfur atom (S) and two oxygen atoms (O). To find the number of moles of [tex]SO_2[/tex] corresponding to [tex]8.02 * 10^{21}[/tex] atoms of oxygen, we first calculate the number of moles of oxygen atoms.
Given: Number of oxygen atoms = [tex]8.02 * 10^{21}[/tex] atoms
Using Avogadro's number ([tex]6.022 * 10^{23}[/tex] atoms/mol), we can convert the number of oxygen atoms to moles:
Number of moles of oxygen = ([tex]8.02 * 10^{21}[/tex] atoms) / ([tex]6.022 * 10^{23}[/tex] atoms/mol) ≈ 0.0133 mol
Since there are two oxygen atoms in one [tex]SO_2[/tex] molecule, the number of moles of [tex]SO_2[/tex] would be half of the number of moles of oxygen:
Number of moles of [tex]SO_2[/tex] = 0.0133 mol / 2 = 0.00665 mol
Therefore, approximately 0.00665 moles of [tex]SO_2[/tex] contain [tex]8.02 * 10^{21}[/tex] atoms of oxygen.
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if the concentration of nacl is 4.90 m, when it begins to crystallize out of solution, then what is the ksp?
The Ksp (solubility product constant) of NaCl when it begins to crystallize out of a solution with a concentration of 4.90 M is [Na+][Cl-] = 4.80 x 10^-8.
What is the solubility product constant (Ksp) when NaCl crystallizes from a 4.90 M solution?When a solution becomes saturated with a solute, it reaches a point where the solute starts to crystallize out of the solution. The solubility product constant (Ksp) is a measure of the maximum amount of a solute that can dissolve in a solvent at a given temperature.
It represents the equilibrium constant for the dissolution of an ionic compound into its constituent ions.
In this case, we are dealing with NaCl, which dissociates into Na+ and Cl- ions in water.
The Ksp expression for NaCl is written as [Na+][Cl-], where the square brackets denote the concentration of each ion in the solution.
When NaCl begins to crystallize out of a solution with a concentration of 4.90 M, the Ksp value can be calculated as [Na+][Cl-] = 4.80 x 10^-8.
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for which of the following reactions does changeH(rxn) represent an enthalpy of formation? a. C(s) + O2(g) = CO2(g) b. CO2(g) + C(s) = 2CO(g) c. CO2(g) + H2(g) = H2O(g) + CO(g) d. 2H2(g) + C(s) = CH4(g)
The enthalpy of formation is represented by ΔH(rxn) for the reaction [tex]C(s) + O_2(g) = CO_2(g)[/tex].
The enthalpy of formation, represented by ΔH(rxn), is the enthalpy change that occurs when one mole of a compound is formed from its constituent elements in their standard states. In option a, the reaction [tex]C(s) + O_2(g) = CO_2(g)[/tex] represents the formation of one mole of carbon dioxide ([tex]CO_2[/tex]) from its elements, carbon (C) and oxygen ([tex]O_2[/tex]). Therefore, ΔH(rxn) for this reaction represents the enthalpy of the formation of [tex]CO_2[/tex].
In options b, c, and d, the reactions involve the formation or decomposition of compounds but not the formation of the given product from its elements. Therefore, ΔH(rxn) for these reactions does not represent the enthalpy of formation. It's important to note that the enthalpy of formation can only be determined for reactions that involve the formation of compounds from their constituent elements.
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In which pair do both compounds exhibit predominantly ionic bonding? A) RbCI and CaO B) PCI_5 and HF C) Kl and O_3 D) Na_2 SO_3 and BH_3 E) NaF and H_2 O
The pair do both compounds exhibit predominantly ionic bonding is A) RbCl and CaO
Ionic bonding occurs when there is a transfer of electrons between atoms, leading to the formation of positive and negative ions that are held together by electrostatic forces. In pair A, RbCl (rubidium chloride) consists of the metal rubidium (Rb) and the nonmetal chlorine (Cl), while CaO (calcium oxide) is made up of the metal calcium (Ca) and the nonmetal oxygen (O).
In both cases, the metal atoms donate electrons to the nonmetal atoms, resulting in the formation of positively charged metal ions and negatively charged nonmetal ions. This transfer of electrons and the subsequent electrostatic attraction between the oppositely charged ions result in ionic bonding. Other pairs in the options contain compounds with either covalent or polar covalent bonds, where electrons are shared between atoms rather than transferred. So therefore the correct answer is A) RbCl and CaO, the pair do both compounds exhibit predominantly ionic bonding
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The design of air bags depends on stoichiometric precision. A compound named sodium azide
(NaN 3 ) quickly decomposes into sodium metal and nitrogen gas. The sodium metal is safely reacted in another
side-reaction, but how many grams of NaN 3 must be included in the air-bag design if they need to inflate the
bag with 65.1 liters of nitrogen gas? Assume the reaction occurs at STP (just an assumption for this problem).
Show your work! Balance the chemical equation. (4 pt)
___NaN 3 ___Na + ___N 2
Approximately 126.1 grams of NaN3 must be included in the airbag design to inflate the bag with 65.1 liters of nitrogen gas.
To balance the chemical equation for the decomposition of sodium azide (NaN3) into sodium metal (Na) and nitrogen gas (N2), we can start by assigning coefficients to each compound:
2 NaN3 -> 2 Na + 3 N2
Now, let's calculate the number of moles of nitrogen gas required to inflate the airbag:
1 mole of a gas at STP occupies approximately 22.4 liters. Therefore, 65.1 liters of nitrogen gas is equal to:
65.1 L / 22.4 L/mol = 2.91 moles of nitrogen gas
From the balanced equation, we can see that 2 moles of NaN3 decompose to produce 3 moles of nitrogen gas. Therefore, the number of moles of NaN3 needed can be calculated using a ratio:
2 moles of NaN3 -> 3 moles of N2
x moles of NaN3 -> 2.91 moles of N2
x = (2.91 moles of N2 * 2 moles of NaN3) / 3 moles of N2
x = 1.94 moles of NaN3
Finally, to calculate the mass of NaN3 needed, we can use its molar mass:
Molar mass of NaN3 = 65 g/mol
Mass of NaN3 = 1.94 moles * 65 g/mol = 126.1 g
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How many grams of chromium metal are plated out when a constant current of 8.00 A is passed through an aqueous solution containing Cr3+ ions for 80.0 minutes?
To calculate the amount of chromium metal plated out, we need to use Faraday's law of electrolysis. The formula is:
Mass (in grams) = Current (in amperes) × Time (in seconds) × Atomic mass of chromium) / (Charge of one electron × Faraday's constant)
First, we convert the time from minutes to seconds: 80.0 minutes × 60 seconds/minute = 4800 seconds.
The atomic mass of chromium is approximately 52 grams/mol, the charge of one electron is 1.6 × 10^-19 coulombs, and Faraday's constant is 96485 C/mol.
Substituting these values into the formula:
Mass = (8.00 A × 4800 s × 52 g/mol) / (1.6 × 10^-19 C × 96485 C/mol)
After calculating, the result is approximately 1.05 grams of chromium metal plated out.
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The amount of chromium metal plated out when a constant current of 8.00 A is passed through an aqueous solution containing Cr³⁺ ions for 80.0 minutes is 3.53 grams.
Determine how to find the amount of chromium plated?To calculate the amount of chromium plated, we can use Faraday's law of electrolysis. The formula is:
Mass (grams) = (Current (A) × Time (s) × Atomic mass of chromium) / (Number of electrons × Faraday's constant)
First, we convert the time from minutes to seconds:
Time = 80.0 minutes × 60 seconds/minute = 4800 seconds
The atomic mass of chromium is 51.9961 g/mol, the number of electrons transferred for Cr³⁺ is 3, and the Faraday's constant is 96,485 C/mol.
Now we can substitute the values into the formula:
Mass (grams) = (8.00 A × 4800 s × 51.9961 g/mol) / (3 electrons × 96,485 C/mol)
After performing the calculations, we find that the mass of chromium plated out is approximately 3.53 grams.
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how many grams of cu (63.55 g/mol) may be deposited from a Cu²⁺ solution during electrolysis by a current of 3.00 A for 7.0 hours? Please report 1 decimal place F=96485 C/mol
Approximately 65.0 grams of copper (Cu) may be deposited from the Cu²⁺ solution during electrolysis by a current of 3.00 A for 7.0 hours.
Given information,
The molar mass of Cu = 63.55 g/mol
Current (I) = 3.00A
Tiem (t) = 7 hours = 7.0 × 3600 seconds
According to Faraday's law of electrolysis:
Mass = (Current × Time × Molar mass) / (Faraday's constant)
Mass = (3 × 7 × 3600 × 63.55) / 96485
Mass ≈ 65.02 grams (rounded to 2 decimal places)
Therefore, approximately 65.0 grams of copper (Cu) may be deposited from the Cu²⁺ solution during electrolysis by a current of 3.00 A for 7.0 hours.
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How many moles of hydrogen do you need
to react with 0. 85 moles of nitrogen?
PLEASE HELP I WILL MARK BRANLIEST
To react with 0.85 moles of nitrogen, you would need 2.55 moles of hydrogen.
The balanced chemical equation for the reaction between hydrogen (H[tex]_{2}[/tex]) and nitrogen (N[tex]_{2}[/tex]) is:
3H[tex]_{2}[/tex] + N[tex]_{2}[/tex] → 2NH[tex]_{3}[/tex]
From the balanced equation, we can see that three moles of hydrogen react with one mole of nitrogen to produce two moles of ammonia (NH[tex]_{3}[/tex]). Therefore, the stoichiometric ratio between hydrogen and nitrogen is 3:1.
Given that we have 0.85 moles of nitrogen, we can calculate the required amount of hydrogen by multiplying the number of moles of nitrogen by the stoichiometric ratio. Thus, 0.85 moles of nitrogen requires 2.55 moles of hydrogen for complete reaction.
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what is the noble gas shorthand electron configuration for y+?
The noble gas shorthand electron configuration for Y+ is [tex][Kr]5s24d1.[/tex]. The noble gas shorthand provides a concise representation of the electron configuration by using the symbol of the noble gas and indicating the additional electrons specific to the element being considered.
To determine the noble gas shorthand electron configuration, we start by locating the noble gas that comes before the element Yttrium (Y) in the periodic table. In this case, the noble gas is Krypton (Kr), which has the electron configuration [tex][Kr]4d^{10}5s^2[/tex] Next, we remove the outermost electrons from Krypton and continue with the electron configuration of Yttrium. Yttrium has an atomic number of 39, which means it has 39 electrons. Yttrium’s electron configuration is [tex]1s^22s^22p^63s^23p^64s^23d^104p^65s^24d^1.[/tex]
To simplify the electron configuration using the noble gas shorthand, we can replace the electron configuration of Yttrium from the beginning with the noble gas Kr. This allows us to represent the inner electrons of Kr without writing them out explicitly. Thus, the noble gas shorthand electron configuration for Y+ is [tex][Kr]5s24d^1.[/tex]
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which of the following compounds is the most reactive dienophile in a diels-alder reaction with 1,3-butadiene? ch3ch≡chch3 ch2= choch3 ch2= ch2 ch2= chcho (ch3)2c=ch2
The most reactive dienophile in a Diels-Alder reaction with 1,3-butadiene is CH2=CHCHO (acrolein)
What Is Diels-Alder reaction? Analyzing The Given Compounds.The Diels-Alder reaction is a chemical reaction that combines a conjugated diene and a dienophile to form a cyclic compound.
The reactivity of a dienophile is determined by its ability to accept electron density and undergo the necessary bond-forming process.
Among the given options, CH2=CHCHO (acrolein) is the most reactive dienophile in a Diels-Alder reaction with 1,3-butadiene. This is because acrolein contains an electron-withdrawing carbonyl group (C=O) attached to an alkene (CH2=CH).
The electron-withdrawing nature of the carbonyl group increases the electrophilic character of the alkene, making it more susceptible to nucleophilic attack by the electron-rich diene, 1,3-butadiene.
The other compounds in the options (CH3CH≡CHCH3, CH2=CHOCH3, CH2=CH2, and (CH3)2C=CH2) lack the electron-withdrawing carbonyl group, reducing their reactivity as dienophiles in a Diels-Alder reaction with 1,3-butadiene.
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aluminum combines with iodine vapor. how many grams of aii3 can be theiretucally formed when 1.00g of aluminum reacts with 12g of iodine
Mass of aluminium (Al) = 1.00g2. Mass of iodine (I₂) = 12g. Aluminium reacts with iodine to form aluminium iodide.2Al + 3I₂ → 2AlI₃. mass of aluminum (Al) = 27 g/mol, Molar mass of iodine (I₂) = 2 × 126.9 g/mol = 253.8 g/mol.
Molar mass of aluminum iodide (AlI₃) = 27 + 3 × 126.9 = 379.7 g/mol.
1. The given reaction equation is 2Al + 3I₂ → 2AlI₃.
The balanced equation suggests that two moles of aluminium react with three moles of iodine to produce two moles of aluminium iodide.
2. Find the number of moles of aluminium and iodine. A number of moles of Al = Given the mass of Al/Molar mass of Al = 1.00 g/27 g/mol = 0.0370 mol, Number of moles of I₂ = Given the mass of I₂/Molar mass of I₂ = 12 g/253.8 g/mol = 0.0473 mol.
3. Calculate the limiting reagent (which is the reactant that is completely consumed). The reaction requires three moles of iodine for every two moles of aluminium.
Thus, aluminium is the limiting reagent since only 0.0370 mol of it is present, and 0.0370 × (3/2) = 0.0555 mol of iodine is required.
But, only 0.0473 mol of iodine is present.
Therefore, all the aluminium will react with 0.0473 mol of iodine
4. Determine the theoretical yield of aluminium iodide in grams. The number of moles of AlI₃ produced = Number of moles of Al reacted = 0.0370 mol. Theoretical yield of AlI₃ = Number of moles of AlI₃ × Molar mass of AlI₃= 0.0370 mol × 379.7 g/mol= 14.04 g.
Therefore, 14.04 grams of AlI₃ can be theoretically formed when 1.00 grams of aluminium reacts with 12 grams of iodine.
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Complete and balance the following nuclear equations by supplying the missing particle:
(a) 252/98Cf + 10/5B -> 3 1/0n + ?
(b) 2/1H + 3/2He -> 4/2He + ?
(c) 1/1H + 11/5B -> 3?
I have the answers, but really need to understand the concept
(a) 252/98Cf + 10/5B [tex]\rightarrow[/tex] 3 1/0n + 4/2He: Alpha particle (4/2He) emitted, Californium (Cf) decays, (b) 2/1H + 3/2He [tex]\rightarrow[/tex] 4/2He + 1/1H: Proton (1/1H) involved, Hydrogen (H) reacts, and (c) 1/1H + 11/5B [tex]\rightarrow[/tex] 3 1/0n + 1 1/?H: Neutron (1/0n) produced, Boron (B) reacts.
(a) The missing particle in the nuclear equation 252/98Cf + 10/5B [tex]\rightarrow[/tex] 3 1/0n + ? is an alpha particle (4/2He).
The balanced nuclear equation is:
252/98Cf + 10/5B [tex]\rightarrow[/tex] 3 1/0n + 4/2He
In this equation, an alpha particle (4/2He) is emitted from the reaction. The resulting product is a neutron (3 1/0n), and the element undergoing the decay is Californium (Cf) with atomic number 98.
(b) The missing particle in the nuclear equation 2/1H + 3/2He [tex]\rightarrow[/tex] 4/2He + ? is a proton (1/1H).
The balanced nuclear equation is:
2/1H + 3/2He [tex]\rightarrow[/tex] 4/2He + 1/1H
In this equation, a proton (1/1H) is involved in the reaction. The resulting product is an alpha particle (4/2He), and the element undergoing the reaction is Hydrogen (H) with atomic number 1.
(c) The missing particle in the nuclear equation 1/1H + 11/5B [tex]\rightarrow[/tex] 3? + ? is a neutron (1/0n).
The balanced nuclear equation is:
1/1H + 11/5B [tex]\rightarrow[/tex] 3 1/0n + 1 1/?H
In this equation, a neutron (1/0n) is produced. The resulting product is unknown (denoted by "?"), and the element undergoing the reaction is Boron (B) with atomic number 5.
Therefore, these nuclear equations represent different types of nuclear reactions, such as alpha decay and nuclear fusion. Understanding the concepts of nuclear reactions and the characteristics of particles involved is crucial for comprehending the behaviour and transformation of atomic nuclei.
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explain the difference in polarity between CO2 and OF2 molecules by referring to the polarity of the bonds of the molecules
10ml of 0.10 m hcl, 5.0 ml of 010 m h2so4 and 0.060 g of naoh are mixed together and diluted to a final volume of 25.0 ml
calculate the ph
When 10 ml of 0.10 M HCl, 5.0 ml of 10 M H₂SO₄, and 0.060 g of NaOH are mixed together and diluted to a final volume of 25.0 ml the pH is -0.599.
How to calculate the pHThe steps followed to calculate the pH of the final solution when 10 mL of 0.10 M HCl, 5.0 mL of 10 M H₂SO₄, and 0.060 g of NaOH are mixed together and then diluted to a final volume of 25.0 mL:
1. Write the balanced chemical equations for the reactions between HCl and NaOH and between H₂SO₄ and NaOH
When 10 mL of 0.10 M HCl, 5.0 mL of 10 M H₂SO₄, and 0.060 g of NaOH are mixed together, two reactions will occur.
The first reaction is between HCl and NaOH, which is a neutralization reaction that produces water and NaCl. The balanced chemical equation for this reaction is: HCl + NaOH -> H₂O + NaCl.The second reaction is between H₂SO₄ and NaOH, which is also a neutralization reaction that produces water and Na₂SO₄. The balanced chemical equation for this reaction is: H₂SO₄ + 2NaOH -> 2H₂O + Na₂SO₄.These two reactions can be combined into a single equation that shows the overall reaction that occurs:
HCl + H₂SO₄ + 3NaOH -> 3H₂O + NaCl + Na₂SO₄2. Calculate the initial number of moles of each reactant:
n(HCl) = C * V = 0.10 M * 0.010 L = 0.001 mol
n(H2SO4) = C * V = 10 M * 0.005 L = 0.050 mol
n(NaOH) = m / M = 0.060 g / 39.997 g/mol ≈ 0.0015 mol
3. Determine the limiting reactant
The limiting reactant is the reactant that is used up first. To determine the limiting reactant, we can compare the number of moles of each reactant to the stoichiometric ratio of the reaction.
The stoichiometric ratio of the reaction is 3NaOH : HCl : H₂SO₄ = 3: 1: 1.The number of moles of NaOH is greater than the number of moles of HCl and H₂SO₄.Therefore, NaOH is the limiting reactant.4. Use the balanced chemical equations to determine the number of moles of products formed and any excess reactants remaining.
From our previous calculations, we know that NaOH is the limiting reactant because it will be consumed first. The initial number of moles of NaOH is approximately 0.0015 mol. According to the balanced chemical equation, three moles of NaOH react with one mole of HCl and one mole of H₂SO₄. Therefore_
0.0015 mol NaOH * (1 mol HCl / 3 mol NaOH) ≈ 0.0005 mol of HCl
0.0015 mol NaOH * (1 mol H₂SO₄ / 3 mol NaOH) ≈ 0.0005 mol of H₂SO₄.
Subtracting the number of moles that reacted from the initial number of moles, we find that there are approximately 0.001 mol - 0.0005 mol = 0.0005 mol of HCl remaining in excess
0.050 mol - 0.0005 mol ≈ 0.0495 mol of H₂SO₄ remaining in excess.
5. Calculate the concentration of excess reactants remaining in the final solution by dividing the number of moles by the final volume of solution:
C(HCl) = n / V = 0.0005 mol / 0.025 L = 0.020 M
C( H₂SO₄) = n / V = 0.0495 mol / 0.025 L = 1.98 M.
6. Calculate the concentration of H+ ions in the final solution by adding the concentrations of HCl and H₂SO₄:
H₂SO₄ is a strong acid that fully ionizes in water, which means that each molecule of H₂SO₄ dissociates to yield two H⁺ ions, so [ H₂SO₄] = 2 * 1.98 = 3.96 M
[H+] = [HCl] + [H2SO4] = 0.020 M + 3.96 M = 3.98 M.
7. Use the formula for calculating pH: pH = -log[H+] to calculate the pH of the final solution: pH ≈ -log(3.98) ≈ -0.599
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how many liters are in 0.967 moles of LiCl
Approximately 0.967 moles of LiCl would occupy around 21.67 liters at STP.
To determine the volume of a given amount of substance, we need to know the molar volume, which is the volume occupied by one mole of the substance. However, the molar volume can vary depending on the conditions, such as temperature and pressure.
Assuming we are dealing with an ideal gas at standard temperature and pressure (STP), the molar volume is approximately 22.4 liters. This value is commonly used for gases in calculations.
Since we are given the amount of substance in moles (0.967 moles of LiCl) and we want to determine the volume in liters, we can use the molar volume as a conversion factor:
0.967 moles LiCl x (22.4 liters/1 mole) ≈ 21.67 liters
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What volume will a gas have at SC, if it has a pressure of 20.00 kPa at -40.00 c, with a volume of 3.000 L? [6.939 x 10^-1 L)
The volume of the gas at standard conditions (STP) would be approximately 0.6939 L, which is equivalent to 6.939 x 10⁻¹ L as rounded to three significant figures.
The volume of a gas at standard conditions (STP), we can use the ideal gas law equation:
PV = nRT
Where:
P is the pressure of the gas
V is the volume of the gas
n is the number of moles of gas
R is the ideal gas constant (0.0821 L·atm/(mol·K))
T is the temperature of the gas in Kelvin
Standard conditions (STP) are defined as a temperature of 0°C (273.15 K) and a pressure of 1 atm (101.3 kPa).
Given:
Pressure (P) = 20.00 kPa
Temperature (T) = -40.00°C = -40.00 + 273.15 = 233.15 K
Volume (V) = 3.000 L
The volume at standard conditions, we need to convert the given pressure and temperature to the appropriate units and then calculate the volume.
Step 1: Convert pressure to atm
20.00 kPa = 20.00 kPa * (1 atm / 101.3 kPa) ≈ 0.197 atm
Step 2: Convert temperature to Kelvin
T = 233.15 K
Step 3: Apply the ideal gas law equation to find the number of moles (n)
PV = nRT
n = (PV) / (RT)
n = (0.197 atm * 3.000 L) / (0.0821 L·atm/(mol·K) * 233.15 K) ≈ 0.0038 mol
Step 4: Apply the ideal gas law equation to find the volume (V) at standard conditions (STP)
PV = nRT
V = (nRT) / P
V = (0.0038 mol * 0.0821 L·atm/(mol·K) * 273.15 K) / 1 atm ≈ 0.6939 L
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a volume of 500.0 ml of 0.120 m naoh is added to 545 ml of 0.250 m weak acid (a=5.44×10−5). what is the ph of the resulting buffer? HA(aq)+OH−(aq)⟶H2O(l)+A−(aq)
The pH of the resulting buffer is approximately 4.229. To determine the pH of the resulting buffer, we need to consider the acid-base reaction between the weak acid (HA) and the strong base (NaOH). The reaction is as follows:
HA(aq) + OH^-(aq) → H2O(l) + A^-(aq)
First, we need to determine the moles of acid (HA) and base (OH^-) present in the solution. We can use the formula:
moles = concentration (molarity) × volume (in liters)
Moles of HA = 0.250 M × 0.545 L = 0.13625 moles
Moles of OH^- = 0.120 M × 0.500 L = 0.060 moles
Since the acid and base react in a 1:1 ratio, we have an excess of acid. This means that the weak acid will act as the buffer component.
Next, we need to calculate the concentration of the weak acid in the buffer solution. To do this, we divide the moles of the weak acid by the total volume of the solution:
Concentration of HA = moles of HA / total volume (in liters) = 0.13625 moles / (0.545 L + 0.500 L) = 0.13625 moles / 1.045 L = 0.1305 M
Now, we can use the Henderson-Hasselbalch equation to calculate the pH of the resulting buffer:
pH = pKa + log([A^-] / [HA])
The pKa of the weak acid is given as 5.44×10^-5.
[A^-] = concentration of the conjugate base = 0.120 M (from the NaOH solution)
[HA] = concentration of the weak acid = 0.1305 M
pH = -log(5.44×10^-5) + log(0.120 M / 0.1305 M) = 4.265 + log(0.920)
Using logarithm properties, we can simplify further:
pH = 4.265 + log(0.920) = 4.265 - 0.036 = 4.229
Therefore, the pH of the resulting buffer is approximately 4.229.
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Estimate the approximate Zeff felt by an electron in the 3s orbital of Na.
Estimate the approximate Zeff felt by an electron in the 2p orbital of Na.
Assume that the shielding of electrons within the same shell is negligible.
I originally put 3.6 and 10.4, respectively, but it said it was wrong so maybe it's supposed to be rounded?
Not sure
Zeff, or effective nuclear charge, refers to the net positive charge experienced by an electron in an atom. It takes into account the attraction of the positively charged nucleus and the repulsion of the negatively charged electrons in the same outer shells. The greater the number of electrons between the nucleus and the electron of interest, the less effective the nuclear charge will be.
For an electron in the 3s orbital of Na, there are two electrons in the 1s orbital and eight electrons in the 2s and 2p orbitals that shield it from the nuclear charge. Thus, the Zeff felt by the 3s electron is approximately equal to the nuclear charge (11) minus the shielding from the 10 inner electrons, which is about 1. Therefore, the approximate Zeff for the 3s electron in Na is 10. For an electron in the 2p orbital of Na, there are two electrons in the 1s orbital, eight electrons in the 2s and 2p orbitals, and one electron in the 3s orbital that shield it from the nuclear charge. Thus, the Zeff felt by the 2p electron is approximately equal to the nuclear charge (11) minus the shielding from the 11 inner electrons, which is about 0. Therefore, the approximate Zeff for the 2p electron in Na is 11. It is important to note that these values are estimates and can vary depending on factors such as the shape of the orbitals and the relative positions of the electrons.
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when and when an object is vibrate in research that it has energy in its kinetic energy something what word completes the sentence.
fill in the left side of this equilibrium constant equation for the reaction of hypobromous acid with water.
For the reaction of hypobromous acid (HOBr) with water, the equilibrium constant equation can be written as follows:
The reaction: HOBr(aq) + H2O(l) ⇌ H3O+(aq) + BrO-(aq)
The equilibrium constant expression (K_a): K_a = [H3O+][BrO-] / [HOBr]
Here, K_a is the acid dissociation constant, which is a specific type of equilibrium constant. This expression represents the ratio of the concentrations of the products (H3O+ and BrO-) to the concentration of the reactant (HOBr) when the reaction has reached equilibrium.
Hypobromous acid (HBrO) is a weak acid that consists of bromine, hydrogen, and oxygen. It is formed when bromine (Br₂) dissolves in water (H₂O) and undergoes a reaction with water molecules.
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Which of the following are ways that we can stabilize carbocations? Choose all that apply.
a. Hyperconjugation
b. Zaitzev's rule
c. Resonance/conjugation
d. Inductive effect
Stabilize carbocations are Hyperconjugation & Resonance/conjugation
Carbocations are electron-deficient species, and therefore, stabilizing them is necessary to prevent them from reacting with nucleophiles or rearranging to form more stable carbocations. Two ways to stabilize carbocations are through hyperconjugation and resonance/conjugation.
Hyperconjugation refers to the delocalization of electrons from a neighboring C-H or C-C bond to the positively charged carbon atom in the carbocation. This delocalization stabilizes the carbocation by increasing its electron density and decreasing its positive charge.
Resonance or conjugation occurs when a carbocation can delocalize its positive charge through a nearby pi bond or lone pair of electrons. This delocalization stabilizes the carbocation by distributing the positive charge over a larger area and lowering its energy.
Zaitsev's rule and the inductive effect do not directly stabilize carbocations but rather affect the stability of the alkene or substrate from which the carbocation is formed.
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. For the reaction C2H6 (g) → C2H4 (g) + H2 (g) ΔH° is +137 kJ/mol and ΔS° is +120 J/K ∙ mol. This reaction is ________.
A) spontaneous at all temperatures
B) spontaneous only at high temperature
C) spontaneous only at low temperature
D) nonspontaneous at all temperatures
The reaction is likely spontaneous only at high temperatures. The correct answer is option B) spontaneous only at high temperature.
For the reaction C2H6 (g) → C2H4 (g) + H2 (g), the given values are ΔH° = +137 kJ/mol and ΔS° = +120 J/K∙mol. To determine if the reaction is spontaneous, we need to calculate the Gibbs free energy change (ΔG°) using the equation ΔG° = ΔH° - TΔS°, where T is the temperature in Kelvin.
Since ΔH° is positive, the reaction is endothermic, meaning it requires energy to proceed. Meanwhile, ΔS° is positive, indicating an increase in disorder or entropy. The sign of ΔG° will determine if the reaction is spontaneous or not. If ΔG° is negative, the reaction is spontaneous; if ΔG° is positive, the reaction is nonspontaneous.
Considering the given ΔH° and ΔS° values, as temperature (T) increases, the TΔS° term will become more significant. If T is high enough, the TΔS° term may overcome the positive ΔH° value, resulting in a negative ΔG° and a spontaneous reaction. On the other hand, at low temperatures, the TΔS° term is less significant, and ΔG° may remain positive, resulting in a nonspontaneous reaction.
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The spontaneity of a reaction can be determined by the Gibbs free energy equation: ΔG° = ΔH° - TΔS°. If ΔG° is negative, the reaction is spontaneous.
Using the given values, ΔG° = +137 kJ/mol - (298 K)(+120 J/K ∙ mol)/1000 = +98.84 kJ/mol. Since ΔG° is positive, the reaction is nonspontaneous at all temperatures. Therefore, the answer is D) nonspontaneous at all temperatures.
The Gibbs free energy is a measure of the maximum amount of reversible work that can be extracted from a system at constant temperature and pressure. If ΔG is negative, the process is spontaneous and can occur without the input of external energy. If ΔG is positive, the process is non-spontaneous and requires the input of energy to occur. If ΔG is zero, the system is in equilibrium. The Gibbs free energy equation is a fundamental equation in thermodynamics that relates the enthalpy (H), entropy (S), and temperature (T) of a system to its Gibbs free energy (G). The equation is given as:
ΔG = ΔH - TΔS
In this equation:
ΔG represents the change in Gibbs free energy.
ΔH represents the change in enthalpy (heat content) of the system.
ΔS represents the change in entropy (disorder) of the system.
T represents the temperature in Kelvin.
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Rank the following compounds in order from most reduced to most oxidized iodine. Most reduced I^2 I3^- IO^- HIO2 Most oxidized
The ranking goes from the most reduced iodine [tex](I^2[/tex]) with an oxidation state of 0 to the most oxidized iodine [tex](HIO2)[/tex] with an oxidation state of +5.
Rank the following compounds from most reduced to most oxidized iodine:[tex]I^2, I3^-, IO^-, HIO2[/tex]?To rank the following compounds in order from most reduced to most oxidized iodine, let's examine the oxidation states of iodine in each compound:
[tex]I^2[/tex]: In this compound, iodine has an oxidation state of 0 since it is in its elemental form.[tex]I3^[/tex]-: In this compound, each iodine atom has an oxidation state of -1, resulting in a total oxidation state of -3 for the iodine ion.[tex]IO^[/tex]-: In this compound, iodine has an oxidation state of -1.[tex]HIO2[/tex]: In this compound, iodine has an oxidation state of +5.Based on the oxidation states, we can now rank the compounds:
Most reduced: I^2 (oxidation state of 0) <[tex]I3^[/tex]- (oxidation state of -1) <[tex]IO^[/tex]- (oxidation state of -1) <[tex]HIO2[/tex] (oxidation state of +5) : Most oxidized
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Two special steps in the Experimental Procedure are incorporated to reduce the loss of calcium oxalate ppt. Identify these steps and the reasons why.
Two special steps in the Experimental Procedure are incorporated to reduce the loss of calcium oxalate ppt are Filtration under reduced pressure and Washing with an appropriate solvent
In the experimental procedure, two special steps are incorporated to reduce the loss of calcium oxalate precipitate. These steps are:
1. Filtration under reduced pressure:
One of the steps to reduce the loss of calcium oxalate precipitate is to perform the filtration under reduced pressure using a Buchner funnel and a vacuum pump. Filtration under reduced pressure enhances the filtration rate by applying suction, which helps remove the liquid portion of the mixture more efficiently. This reduces the contact time between the precipitate and the liquid, minimizing the chances of loss through solubility or adhesion to the filter paper. Additionally, the reduced pressure aids in maintaining the integrity of the precipitate during filtration.
2. Washing with an appropriate solvent:
Another step to minimize the loss of calcium oxalate precipitate involves washing the precipitate with an appropriate solvent. This is typically done using a solvent like water or ethanol to rinse the precipitate on the filter paper. The washing step helps remove any impurities or soluble contaminants that may be present in the precipitate. By washing the precipitate, it ensures that only the desired calcium oxalate remains on the filter paper, reducing potential loss during subsequent drying or handling processes.
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Given the following equilibrium reaction: 2 SO2 (g) + O2 = 2 SO3 (g) Initially 2.99 moles of SO2 and 3.16 moles of O2 was added to a flask at 22°C. If at equilibrium the amount of SO2 was found to be 0.471 moles, what is the amount of O2 at equilibrium? Answer to 3 decimal places.
The amount of O₂ at equilibrium is approximately 4.4195 moles.
Write the chemical formulas in subscripts "To determine the amount of O₂ at equilibrium, we can use the stoichiometry of the balanced equation and the given information.
The balanced equation is:
2 SO₂ (g) + O₂ ⇌ 2 SO₃ (g)
From the balanced equation, we can see that the stoichiometric ratio between SO₂ and O₂ is 2:1. This means that for every 2 moles of SO₂ reacted, 1 mole of O₂ is consumed.
Let's calculate the moles of SO₂ that reacted based on the given information:
Initial moles of SO₂ = 2.99 moles
Moles of SO₂ at equilibrium = 0.471 moles
Change in moles of SO₂ = Initial moles of SO₂ - Moles of SO₂ at equilibrium
= 2.99 moles - 0.471 moles
= 2.519 moles
According to the stoichiometry of the balanced equation, this change in moles of SO₂ corresponds to half the change in moles of O₂.
Change in moles of O₂ = (1/2) × Change in moles of SO₂
= (1/2) × 2.519 moles
= 1.2595 moles
To find the moles of O₂ at equilibrium, we need to add the change in moles of O₂ to the initial moles of O₂:
Moles of O₂ at equilibrium = Initial moles of O₂ + Change in moles of O₂
= 3.16 moles + 1.2595 moles
= 4.4195 moles
Therefore, the amount of O₂ at equilibrium is approximately 4.4195 moles.
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Which of the following statements regarding oxidation-reduction reactions is correct?
Oxidation-reduction reactions involve sharing electrons.
Oxidation can occur without reduction.
You can tell that a substance is oxidized if it loses electrons.
You can tell that a substance is reduced if its oxidation number increases.
None of these statements is correct.
The correct statement regarding oxidation-reduction reactions is: Oxidation-reduction reactions involve sharing electrons.
Oxidation reaction is a type of chemical reaction in which there is removal electron, removal of hydrogen and some time there is a loss of electropositive radicals takes place.Oxidation is the loss of electrons by an atom, ion, or molecule. The atom, ion, or molecule that is oxidized will become more positively charged. Oxidation may also involve the addition of oxygen or the loss of hydrogen.Oxidation–reduction reactions, commonly known as redox reactions, are reactions that involve the transfer of electrons from one species to another. The species that loses electrons is said to be oxidized, while the species that gains electrons is said to be reduced.
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find the solubility of cui in 0.53 m kcn solution. the ksp of cui is 1.1×10−12 and the kf for the cu(cn)2− complex ion is 1×1024 .
The solubility of CuI in the 0.53 M KCN solution is approximately [tex]3.39*10^{-26} M[/tex].
Determine the solubility.
To find the solubility of CuI (copper(I) iodide) in a 0.53 M KCN solution, we need to consider the formation of the complex ion [tex]Cu(CN)2^-[/tex]. First, we will determine if CuI will dissolve to a significant extent by comparing the solubility product constant (Ksp) of CuI with the formation constant (Kf) of the [tex]Cu(CN)2^-[/tex] complex ion. If the formation of the complex is favored, the solubility of CuI will decrease.
The balanced equation for the dissolution of CuI can be written as:
[tex]CuI(s)[/tex] ⇌ [tex]Cu^+(aq) + I^-(aq)[/tex]
The solubility product constant expression is given by:
[tex]Ksp = [Cu^+][I^-][/tex]
The formation of the [tex]Cu(CN)2^-[/tex] complex ion can be represented by the equation:
[tex]Cu^+(aq) + 2CN^-(aq)[/tex] ⇌ [tex]Cu(CN)2^-[/tex](aq)
The formation constant expression is given by:
[tex]Kf = [Cu(CN)2^-] / [Cu^+][CN^-]^2[/tex]
To find the solubility of CuI in the KCN solution, we need to determine the concentration of [tex]Cu^+[/tex] ions when it is present as the complex ion [tex]Cu(CN)2^-[/tex]. This can be done using an ICE (Initial, Change, Equilibrium) table.
Let's assume the solubility of CuI is "s" moles per liter. Then the concentration of [tex]Cu^+[/tex] ions and [tex]I^-[/tex] ions will both be "s" M.
Using the formation constant expression, we can write:
[tex]Kf = [Cu(CN)2^-] / [Cu^+][CN^-]^2\\1*10^{24} = [Cu(CN)2^-] / (s)(0.53)^2\\[Cu(CN)2^-] = 1*10^{24} * (s)(0.53)^2[/tex]
Using the solubility product constant expression, we can write:
[tex]Ksp = [Cu^+][I^-]1.1*10^-12 = (s)(s)[/tex]
Since we assume s as the solubility, the concentration of [tex]Cu^+[/tex] ions is also "s" M.
Now, equating the expressions for [tex][Cu^+][/tex], we have:
[tex]s = (1*10^24)(s)(0.53)^2[/tex]
Simplifying the equation:
[tex]1 = (1*10^{24})(0.53)^2[/tex]
Solving for s:
[tex]s = 1 / [(1*10^{24})(0.53)^2][/tex]
Evaluating the expression:
[tex]s = 3.39 * 10^{-26} M[/tex] (approx)
Therefore, the solubility of CuI in the 0.53 M KCN solution is approximately [tex]3.39*10^{-26} M[/tex].
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