The question is missing. Here is the complete question.
Which balanced redox reaction is ocurring in the voltaic cell represented by the notation of [tex]Al_{(s)}|Al^{3+}_{(aq)}||Pb^{2+}_{(aq)}|Pb_{(s)}[/tex]?
(a) [tex]Al_{(s)}+Pb^{2+}_{(aq)} ->Al^{3+}_{(aq)}+Pb_{(s)}[/tex]
(b) [tex]2Al^{3+}_{(aq)}+3Pb_{(s)} -> 2Al_{(s)}+3Pb^{2+}_{(aq)}[/tex]
(c)[tex]Al^{3+}_{(aq)}+Pb_{(s)} ->Al_{(s)}+Pb^{2+}_{(aq)}[/tex]
(d) [tex]2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}[/tex]
Answer: (d) [tex]2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}[/tex]
Explanation: Redox Reaction is an oxidation-reduction reaction that happens in the reagents. In this type of reaction, reagent changes its oxidation state: when it loses an electron, oxidation state increases, so it is oxidized; when receives an electron, oxidation state decreases, then it is reduced.
Redox reactions can be represented in shorthand form called cell notation, formed by: left side of the salt bridge (||), which is always the anode, i.e., its half-equation is as an oxidation and right side, which is always the cathode, i.e., its half-equation is always a reduction.
For the cell notation: [tex]Al_{(s)}|Al^{3+}_{(aq)}||Pb^{2+}_{(aq)}|Pb_{(s)}[/tex]
Aluminum's half-equation is oxidation:
[tex]Al_{(s)} -> Al^{3+}_{(aq)}+3e^{-}[/tex]
For Lead, half-equation is reduction:
[tex]Pb^{2+}_{(aq)}+2e^{-} -> Pb_{(s)}[/tex]
Multiply first half-equation for 2 and second half-equation by 3:
[tex]2Al_{(s)} -> 2Al^{3+}_{(aq)}+6e^{-}[/tex]
[tex]3Pb^{2+}_{(aq)}+6e^{-} -> 3Pb_{(s)}[/tex]
Adding them:
[tex]2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}[/tex]
The balanced redox reaction with cell notation [tex]Al_{(s)}|Al^{3+}_{(aq)}||Pb^{2+}_{(aq)}|Pb_{(s)}[/tex] is
[tex]2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}[/tex]
It would require ? Liters of water to dissolve 36 grams of the substance.
The correct answer is 3 liters
Explanation:
If a substance has a solubility of [tex]12 \frac{grams}{liter}[/tex], this means in 1 liter, the grams that can be dissolved are 12 grams. Now, considering Justin and Ellie need to dissolve 36 grams to calculate the number of liters just divide the total of grams into 12 as each liter dissolves only 12 grams. The process is shown below:
36 grams (the amount that will be dissolved) ÷ 12 (grames dissolved per liter) = 3 liters (liters to dissolved 36 grams)
Answer:
It would be 3 liters
Explanation:
How many moles of gaseous boron trifluoride, BF3, are contained in a 4.3421 L bulb at 787.9 K if the pressure is 1.218 atm?
Answer:
The amount of moles of gaseous boron trifluoride, BF₃, contained in a 4.3421 L bulb at 787.9 K if the pressure is 1,218 atm is 0.082 moles
Explanation:
An ideal gas is a theoretical gas that is considered to be made up of point particles that move randomly and do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.
The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:
P*V = n*R*T
where P is the gas pressure, V is the volume that occupies, T is its temperature, R is the ideal gas constant, and n is the number of moles of the gas.
In this case:
P= 1.218 atmV= 4.3421 Ln= ?R= 0.082 [tex]\frac{atm*L}{mol*K}[/tex]T= 787.9 KReplacing:
1.218 atm* 4.3421 L= n*0.082 [tex]\frac{atm*L}{mol*K}[/tex] *787.9 K
Solving:
[tex]n=\frac{1.218 atm* 4.3421 L}{0.082 \frac{atm*L}{mol*K}*787.9 K}[/tex]
n= 0.082 moles
The amount of moles of gaseous boron trifluoride, BF₃, contained in a 4.3421 L bulb at 787.9 K if the pressure is 1,218 atm is 0.082 moles
A baseball has a mass of 0.145 kilograms. If acceration due to gravity is 9.8m/s,what is the weight of the baseball in newtons?
Answer:
I hope it works
Explanation:
As we know that
w=m*g
given m=0.145 , g=9.8
hence we get
w= (9.8)*(0.145)
w=1.421 m/sec 2
if its help-full thank hit the stars and brain-list it thank you
Consider the following reaction at 298K.
I2 (s) + Pb (s) = 2 I- (aq) + Pb2+ (aq)
Which of the following statements are correct?
Choose all that apply.
ΔGo > 0
The reaction is product-favored.
K < 1
Eocell > 0
n = 2 mol electrons
B-
Answer:
Eªcell > 0; n = 2
Explanation:
The reaction:
I2 (s) + Pb (s) → 2 I- (aq) + Pb2+ (aq)
Is product favored.
A reaction that is product favored has ΔG < 0 (Spontaneous)
K > 1 (Because concentration of products is >>>> concentration reactants).
Eªcell > 0 Because reaction is spontaneous.
And n = 2 electrons because Pb(s) is oxidizing to Pb2+ and I₂ is reducing to I⁻ (2 electrons). Statements that are true are:
Eªcell > 0; n = 2Draw a structure for an alcohol that exhibits a molecular ion at M+ = 88 and that produces fragments at m/z = 73, m/z = 70 and m/z = 59.
Answer:
3-pentanol
Explanation:
In this case, we have alcohol as the main functional group (OH) with a molecular ion at 88. If the molecular ion is 88 the molar mass is also 88 g/mol therefore the formula for the unknown molecule is [tex]C_5H_1_2O[/tex].
Additionally, if the mass spectrum shows the molecular ion peak we can not have tertiary alcohols (tertiary alcohols often do not show M+ at all). So, the structures only can be primary and secondary structures.
With this in mind, our options are:
-) 1-pentanol
-) 2-pentanol
-) 3-pentanol
Now we can analyze each structure:
-) 1-pentanol
The structure must explain all the fragments produced (73, 70, and 59). In this primary alcohol, we will have an alpha cleavage (the red bond would be broken). If this has to happen, we will have fragments at 31 and 57. These fragments dont fit with the reported ones, therefore this is not a possible structure (See figure 1).
-) 2-pentanol
On this structure, we will have also an alpha cleavage (red bond). In this rupture we will have fragments at 45 and 43, these m/z values dont fit with the reported ones, therefore this is not a possible structure (See figure 1).
-) 3-pentanol
In this structure, we have the "OH" bonded to carbon three. So, we can analyze each fragment:
-) m/z 59
This fragment, can be explained as an alpha cleavage. But, in this case we have two ruptures that can produce the same ion. The carbons on both sides of the C-OH bond.
-) m/z 71
This fragment, can be explained as a loss of water (M-18) in which we have the production of a carbocation in the carbon where we previously have the C-OH bond.
-) m/z 73
This fragment, can be explained as a beta cleavage. But, in this case, also we have two ruptures that can produce the same ion. The methyl groups on each end molecule.
See figure 2
I hope it helps!
How has the work of chemists affected the environment over the years?
Answer:
Chemistry is one of the causes for global warming, and in some cases it can even cause certain illnesses.
Answer:
Chemists have both hurt the environment and helped the environment by their actions.
Explanation:
<3
A reaction mechanism has the following proposed elementary steps:Step 1: A → B + CStep 2: A + B → DStep 3: 2 A + D → C + EIf Step 2 is the rate-limiting step, what would the proposed rate law for this mechanism be?
Answer: [tex]Rate=k[A][B][/tex]
Explanation:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.
Order of the reaction is defined as the sum of the concentration of terms on which the rate of the reaction actually depends. It is the sum of the exponents of the molar concentration in the rate law expression.
For reactions which takes place in multiple steps are complex reactions and the order is given by the slowest step which is the rate limiting step.
For the given reaction, the rate limiting step is
[tex]A+B\rightarrow D[/tex]
Rate law will be , [tex]Rate=k[A][B][/tex]
Based on relative bond strengths, classify these reactions as endothermic (energy absorbed) or exothermic (energy released).
Strongest Bond
A-B
A-A
B-B
C-C
B-C
A-C
1. A2 + C2 rightarrow 2AC
2. B2 + C2 rightarrow 2BC
3. A + BC rightarrow AB + C
4. A2 + B2 rightaarrow 2AB
5. AB + C rightarrow AC + B
a. endothermic
b. exothermic
Answer:
1. Exothermic 2. Exothermic 3. Endothermic 4. Endothermic 5. Exothermic.
Explanation:
1. An A-A and a C-C bond results in 2 A-C bonds which are lower than the A-A and C-C bonds so this reaction is exothermic.
2. A B-B bond and a C-C bond results in 2 B-C bonds which are lower than the first 2 bonds so this reaction is also exothermic.
3. There is no bond for single A, a single B-C bond results in a A-B bond and a C molecule. A-B bond is stronger than the B-C bond so the reaction absorbed energy along the way. This shows that it is endothermic.
4. An A-A bond and a B-B bond results in 2 A-B bonds which are stronger than the first two bonds so this reaction is also endothermic.
5. An A-B bond and a C molecule result in an A-C bond and a B molecule. A-C bond is weaker than the A-B bond so there is energy released. This reaction is exothermic.
I hope this answer helps.
Calculate the pH of a buffer that is 0.13 M in lactic acid and 0.10 M in sodium lactate. Express your answer using two decimal places.
Answer:
pH of the buffer is 3.75
Explanation:
It is possible to find pH of a buffer using Hendersson-Hasselbalch equation:
pH = pKa + log [A⁻] / [HA]
Where [A⁻] is molar concentration of the conjugate base and [HA] concentration of the weak acid
In the lactic buffer, pKa = 3.86. Lactic acid is the weak acid and its conjugate base is tha lactate salt. H-H equation for this buffer is:
pH = 3.86 + log [Lactate] / [Lactic acid]
Replacing with the concentrations of the problem:
pH = 3.86 + log [0.10M] / [0.13M]
pH = 3.75
pH of the buffer is 3.75
Which of the following elements can't have an expanded octet? answers A. oxygen B. phosphorous C. chlorine d. sulfer
answer is oxygen .
oxygen is an exception in octet rule
Among the following given elements,oxygen is an element which cannot have an expanded octet.
What is an expanded octet?Expanded octet is a condition where an octet has more than 8 electrons and which is called as hyper-valency state. This concept is related to hybrid orbital theory and Lewis theory. Hyper-valent compounds are not less common and are of equal stability as the compounds which obey octet rule.
Expansion of octet is possible for elements from third period on wards only as they have low-lying empty d - orbitals which can accommodate more than eight electrons.
Expanded octet is not applicable to oxygen as it is second period of periodic table and has less than ten electrons and even does not have the 2d -orbitals due to which it does not fulfill the criteria of an element to have an expanded octet.
Learn more about expanded octet, here:
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What is the rate constant of a reaction if rate = 1 x 10-2 (mol/L)/s, [A] is 2 M,
[B] is 3 M, m = 2, and n = 1?
Answer:
[tex]0.10 \text{ L$^2$mol$^{-2}$s$^{-1}$}[/tex]
Explanation:
The general formula for a rate law is
[tex]\text{rate} = k\text{[A]}^m \text{[B]}^{n}[/tex]
With your numbers, the rate law becomes
1.2 mol·L⁻¹s⁻¹ = k(2 mol·L⁻¹)²(3 mol·L⁻¹)¹ = k × 4 mol²L⁻² × 3 mol·L⁻¹
= 12k mol³L⁻³
[tex]\\ k = \dfrac{\text{1.2 mol $\cdot$ L$^{-1}$s$^{-1}$} }{12\text{ mol$^{3}$L}^{-3}} = \mathbf{0.10} \textbf{ L$\mathbf{^2}$mol$^{\mathbf{-2}}$s$^{\mathbf{-1}}$}[/tex]
Calculate the molarity of a solution containing 29g of glucose (C 6 H 12 O 6 ) dissolved in 24.0g of water. Assume the density of water is 1.00g/mL.
Answer:
whats the ph ofpoh=9.78
Explanation:
What is the compound formed from the combination of the base and a hydrogen ion
Answer:
Water
Explanation:
When a base react to and hydrogen ion, we can produce water.
According to these equation
H⁺ + OH⁻ ⇄ H₂O Kw: 1×10¹⁴
Remember that OH⁻ is determined by a strong base.
This reaction is called neutralization. You can also produce water with a weak base, because OH⁻ are released. For example, let's mention ammonia which is a weak base, it takes protons from water (H⁺)
NH₃ + H₂O ⇄ OH⁻ + NH₄⁺ Kb
When the ammonium ion (acid), reacts to a base, you produce water.
NH₄⁺ + NaOH → NH₃ + H₂O + Na⁺
PV = nRT. If P = 1 atm, V = 5.0 liter, R = 0.0821 L.atm/mol.K, and T = 293 K; what is the value of n?
Answer:
n = 0.207 mole
Explanation:
We have,
P = 1 atm
V = 5 liter
R = 0.0821 L.atm/mol.K
T = 293 K
We need to find the value of n. The relation is as follows :
PV = nRT
Solving for n,
[tex]n=\dfrac{PV}{RT}\\\\n=\dfrac{1\times 5}{0.0821 \times 293}\\\\n=0.207\ \text{mol}[/tex]
So, the value of n is 0.207 mol.
Why can gasses change volume?
A. The forces holding the gas particles together are
stronger than gravity.
B. The gas particles have no mass, so they can change volume.
C. Gravity has no effect on gas particles, so they can float away.
O D. There are no forces holding the gas particles together.
Answer:
There are no forces holding the gas particles together.
Explanation:
Both chlorine and fluorine are represented by a green modeling piece that has 4 holes. Is using the same piece for two different atoms acceptable? Why or why not
Answer:
Yes, same piece can be used.
Explanation:
The same piece can be used for two different atoms are acceptable because both atoms has 7 electrons in their outermost valance shell. Both atoms belong to same group i. e. halogens so same piece can be used for both atoms. If the atoms belong to different groups and they have different number of electrons in their outermost shell so using same piece will be a problem so it is recommended to use different pieces for different atoms.
The use of the same modeling piece for chlorine and fluorine has been accepted as it has consisted of the same properties and belongs to the same group.
Chlorine and fluorine have been the elements of group 17. The elements are halogens with the presence of 7 valence electrons.
The elements have been belonging to the same group and have the same number of valence electrons thus resembling each other in the chemical properties.
Since both the elements are similar to each other, the use of the same piece for two different atoms has been acceptable.
For more information about the modeling piece, refer to the link:
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Which ONE of these cations has the same number of unpaired electrons as Fe2+ ? A) Ni2+ B) Fe3+ C) Cr2+ D) Mn2+ E) Co2+
Answer:
Explanation:
Fe2+ Has 4 unpaired electrons.
By method of elimination;
Option A: Ni2+ has two unpaired electrons. so this option is wrong.
Option B: There are 5 unpaired electrons in the Fe3+ ion. so this option is wrong.
Option C: There are 4 unpaired electrons in the Cr2+ ion. so this option is correct.
Option D: There are 5 unpaired electrons in the Mn2+ ion. so this option is wrong.
Option E: There are 3 unpaired electrons in the Co2+ ion. so this option is wrong.
A solution of HCOOH has 0.16M HCOOH at equilibrium. The Ka for HCOOH is 1.8×10−4. What is the pH of this solution at equilibrium? Express the pH numerically.
Answer:
[tex]pH=2.28[/tex]
Explanation:
Hello,
In this case, for the acid dissociation of formic acid (HCOOH) we have:
[tex]HCOOH(aq)\rightarrow H^+(aq)+HCOO^-(aq)[/tex]
Whose equilibrium expression is:
[tex]Ka=\frac{[H^+][HCOO^-]}{[HCOOH]}[/tex]
That in terms of the reaction extent is:
[tex]1.8x10^{-4}=\frac{x*x}{0.16-x}[/tex]
Thus, solving for [tex]x[/tex] which is also equal to the concentration of hydrogen ions we obtain:
[tex]x=0.00528M[/tex]
[tex][H^+]=0.00528M[/tex]
Then, as the pH is computed as:
[tex]pH=-log([H^+])[/tex]
The pH turns out:
[tex]pH=-log(0.00528M)\\\\pH=2.28[/tex]
Regards.
2. Which one is the odd one
out and why?
o Water
• Hydrogen
Chlorine
o Aluminum
Answer:
Reaction of Chlorine with Hydrogen Chlorine and Hydrogen mixed together explodes when exposed to sunlight, which produces Hydrogen Chloride. In the dark away from sunlight, no reaction occurs, so light energy is required for a reaction. Cl2 + H2 = 2 HCl Reaction of Chlorine with Non-Metals Chlorine directly combines with most non-metals.
Explanation:
I hope this helps bro
2.Which of the alcohols listed below would you expect to react most rapidly with PBr3?A)CH3CH2CH2CH2CH2CH2OHB)(CH3CH2)2CH(OH)CH2CH3C)(CH3CH2)2CHOHCH3D)(CH3CH2)3COHE)(CH3CH2)2C(CH3)OH
Answer:
A) CH3CH2CH2CH2CH2CH2OH
Explanation:
For this question, we have the following answer options:
A) CH3CH2CH2CH2CH2CH2OH
B) (CH3CH2)2CH(OH)CH2CH3
C) (CH3CH2)2CHOHCH3
D) (CH3CH2)3COH
E) (CH3CH2)2C(CH3)OH
We have to remember the reaction mechanism of the substitution reaction with [tex]PBr_3[/tex]. The idea is to generate a better leaving group in order to add a "Br" atom.
The [tex]PBr_3[/tex] attacks the "OH" generation new a bond to P (O-P bonds are very strong), due to this new bond we will have a better leaving group that can remove the oxygen an allow the attack of the Br atom to generating a new C-Br bond. This is made by an Sn2 reaction. Therefore we will have a faster reaction with primary substrates. In this case, the only primary substrate is molecule A. So, "CH3CH2CH2CH2CH2CH2OH" will react faster.
See figure 1
I hope it helps!
How did Jesseca Kusher create her new material?
Answer:
Jesseca Kusher, an 18-year-old researcher from Spartansburg, S.C., invented a paint-on coating for roofing shingles. Her formula could reduce a home's cooling costs and possibly cut ozone pollution in urban areas...
SUPPORT ME ...........
Answer:
Jesseca created mixtures containing graphite, gypsum, and mica that could be painted on roof shingles.
Explanation:
Hope this helped!!
How many equivalent resonance structures can be drawn for the molecule of SO3 without having to violate the octet rule on the sulfur atom
Answer:
3
Explanation:
Resonance is a valence bond concept put forward by Linus Pauling to explain the fact that the observed properties of a molecule may be as a result of the fact that its actual structure lie somewhere between a given number of structural extremes called canonical structures or resonance structures.
There are three resonance structures for SO3 that obey the octet rule. All the S-O bonds in SO3 are equivalent in these resonance structures.
Seven equivalent resonance structures for the molecular of SO3 can be drawn without breaking the octet rule.
We can arrive at this answer because:
The octet rule is a rule that states that an atom must reach stability when it has eight electrons in the valence layer.This means that in bonds that cause the donation or sharing of electrons between atoms, each atom has eight electrons in the valence layer.In chemistry, resonance is a term that refers to structures created to represent the donation or sharing of electrons between the atoms of a molecule.These structures can be arranged in different ways, as long as they respect the octet rule.In an SO3 molecule, electrons are shared between atoms. This sharing can be done with seven resonance structures.
These structures are shown in the figure below.
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A rock has a mass of 15.8 g and causes the water level in a graduated cylinder to raise from 22.3 mL to 32.5 mL. What is the density of the rock in Kg/mL?
Answer:
Explanation:
mass - 15.8 g = 0.0158 kg
volume = 32.5 - 22.5 = 10.2 ml
density = mass / volume
= 0.0158 / 10.2
= 0.00154 kg/ml
hope this helps
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Does a reaction occur when aqueous solutions of potassium hydroxide and chromium(III) bromide are combined
Explanation:
Potassium hydroxide = KOH
Chromium(iii)bromide = CrBr3
Yes! A reaction occurs. This is given by the balanced equation;
3 KOH + CrBr3 → 3 KBr + Cr(OH)3
If 11.2 g of naphthalene, C10H8, is dissolved in 107.8 g of chloroform, CHCl3, what is the molality of the solution
Answer:
CHC12
Explanation:
i am not really sure i am onna do a quick research 4 u tho
Which solution, if either, would create the higher osmotic pressure (compared to pure water): one prepared from 1.0 g of NaCl in 10 mL of water or 1.0 g of CsBr in 10 mL of water
Answer: NaCl would give the higher pressure
Explanation:
Osmotic pressure depends only on the number of ions.
NaCl dissociates as Na+ and Cl- ; CsBr dissociates as Cs+ and Br-
But the concentration of the solutions are different.
Concentration (morality ) of NaCl = Moles /Litre = (1 g /58.44g/mol)/0.01L
Total number of ions in NaCl solution = 2 x (1 g /58.44g/mol)/0.01L ( 1 mol NaCl gives 2 moles ions, 1 mol Na+ and 1 mol Cl-)
= 1.71×2RT
Similarly total number of ions in CsBr solution = 2 x (1 g /212.80 g/mol)/0.01L
= 0.47×2RT
Therefore osmotic pressure is higher in NaCl solution.
When equation for neutralization of HBr by Ca(OH)2 is correctly balanced, how many molecules of water will be formed
Answer:
When equation for neutralization of HBr by Ca(OH)₂ is correctly balanced, 1.2046*10²⁴ molecules of water will be formed
Explanation:
A neutralization reaction is one in which an acid (or acidic oxide) reacts with a base (or basic oxide). In the reaction a salt is formed and in most cases water is formed. A Salt is an ionic compound formed by the union of ions and cations through ionic bonds.
In the reactions of a strong acid (those substances that completely dissociate) with a strong base (they dissociate completely, giving up all their OH-), the complete neutralization of the species is carried out:
2 HBr (aq) + Ca(OH)₂ (s) → CaBr₂ (aq) + 2 H₂O (l)
The reaction is already balanced, complying with the law of conservation of matter. This law states that since no atom can be created or destroyed in a chemical reaction, the number of atoms that are present in the reactants must be equal to the number of atoms present in the products.
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), 2 moles of water H₂O are formed.
On the other hand, Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023 * 10²³ particles per mole. Avogadro's number applies to any substance.
Then you can apply the following rule of three: if 1 mole of H₂O contains 6.023*10²³ molecules, 2 moles of H₂O, how many molecules does it contain?
[tex]amount of molecules=\frac{2moles*6.023*10^{23}molecules }{1 mole}[/tex]
amount of molecules= 1.2046*10²⁴ molecules
When equation for neutralization of HBr by Ca(OH)₂ is correctly balanced, 1.2046*10²⁴ molecules of water will be formed
A buffer is prepared such that [H2PO4-] = 0.095M and [HPO42-] = 0.125M? What is the pH of this buffer solution? (pKa = 7.21 for H2PO4-)
Answer:
pH of the buffer is 7.33
Explanation:
The mixture of the ions H₂PO₄⁻ and HPO₄²⁻ produce a buffer (The mixture of a weak acid, H₂PO₄⁻, with its conjugate base, HPO₄²⁻).
To find pH of a buffer we use H-H equation:
pH = pka + log [A⁻] / [HA]
Where A⁻ is conjugate base and HA weak acid.
For the H₂PO₄⁻ and HPO₄²⁻ buffer:
pH = pka + log [HPO₄²⁻] / [H₂PO₄⁻]
Computing values of the problem:
pH =7.21 + log [0.125M] / [0.095M]
pH = 7.33
pH of the buffer is 7.33
If you have 2.4L of SO2 gas (at STP) how many moles of sulfur dioxide do you have?
Answer:
0.107 mole of SO2.
Explanation:
1 mole of a gas occupy 22.4 L at standard temperature and pressure (STP).
With the above information, we can simply calculate the number of mole of SO2 that will occupy 2.4 L at STP.
This can be obtained as follow:
22.4 L contains 1 mole of SO2.
Therefore, 2.4 L will contain = 2.4/22.4 = 0.107 mole of SO2.
Therefore, 0.107 mole of SO2 is present in 2.4 L at STP.
How to do q solution, qrxn, moles of Mg , and delta Hrxn?
Answer:
14, 508J/K
ΔHrxn =q/n
where q = heat absorbed and n = moles
Explanation:
m = mass of substance (g) = 0.1184g
1 mole of Mg - 24g
n moles - 0.1184g
n = 0.0049 moles.
Also, q = m × c × ΔT
Heat Capacity, C of MgCl2 = 71.09 J/(mol K)
∴ specific heat c of MgCL2 = 71.09/0.0049 (from the formula c = C/n)
= 14, 508 J/K/kg
ΔT= (final - initial) temp = 38.3 - 27.2
= 11.1 °C.
mass of MgCl2 = 95.211 × 0.1184 = 11.27
⇒ q = 11.27g × 11.1 °C × 14, 508 j/K/kg
= 1,7117.7472 J °C-1 g-1
∴ ΔHrxn = q/n
=1,7117.7472 ÷ 0.1184
= 14, 508J/K
