Answer:
1.52M in NaCl
Explanation:
Molarity = moles solute / volume solution in Liters
=> molarity (M) = 3.8 moles / 2.5 Liters solution = 1.52 molar solution in NaCl
Answer: 1.52
Explanation:
How many moles of O2 are needed to react completely with 35 moles of FeCl3? 4FeCl3 + 3O2 > 2Fe2O3 + 3Cl2
Answer:
26 mol
Explanation:
Step 1: Write the balanced equation
4 FeCl₃ + 3 O₂ ⇒ 2 Fe₂O₃ + 3 Cl₂
Step 2: Determine the appropriate molar ratio
The molar ratio of FeCl₃ to O₂ is 4:3.
Step 3: Use the determined molar ratio to calculate the moles of oxygen required to completely react with 35 moles of ferric chloride
[tex]35molFeCl_3 \times \frac{3molO_2}{4molFeCl_3} = 26molO_2[/tex]
Answer:
[tex]n_{O_2}=26.25molO_2[/tex]
Explanation:
Hello,
In this case, given the reaction:
[tex]4FeCl_3 + 3O_2 \rightarrow 2Fe_2O_3 + 6Cl_2[/tex]
Since oxygen and iron (III) chloride are in a 4:3 molar ratio, he required moles of oxygen to completely react with 35 moles of iron (III) chloride result:
[tex]n_{O_2}=35molFeCl_3*\frac{3molO_2}{4molFeCl_3} \\\\n_{O_2}=26.25molO_2[/tex]
Best regards.
What is the pH of a 1.4 M pyridine solution that has Kb = 1.7 × 10-9? The equation for the dissociation of pyridine is C5H5N(aq) + H2O(l) ⇌ C5H5NH+(aq) + OH-(aq). What is the pH of a 1.4 M pyridine solution that has Kb = 1.7 × 10-9? The equation for the dissociation of pyridine is C5H5N(aq) + H2O(l) ⇌ C5H5NH+(aq) + OH-(aq). 4.31 9.69 8.72 10.69
Answer:
pH = 9.69
Explanation:
When pyridine (C₅H₅N) is added to water, the equilibrium that occurs is:
C₅H₅N(aq) + H₂O(l) ⇌ C₅H₅NH⁺(aq) + OH⁻(aq) Kb = 1.7x10⁻⁹
Where Kb is defined as:
Kb = 1.7x10⁻⁹ = [C₅H₅NH⁺] [OH⁻] / [C₅H₅N]
If you have a solution of 1.4M C₅H₅N, the equilibrium concentration of each specie is:
[C₅H₅N] = 1.4 - X
[C₅H₅NH⁺] = X
[OH⁻] = X
Where X represents the reaction coordinate
Replacing in Kb expression:
1.7x10⁻⁹ = [X] [X] / [1.4 - X]
2.38x10⁻⁹ - 1.7x10⁻⁹X = X²
0 = X² + 1.7x10⁻⁹X - 2.38x10⁻⁹
Solving for X:
X = -0.0000488M → False answer, there is no negative concentrations
X = 0.0000488M → Right answer
Thus, [OH⁻] = 0.0000488M. As pOH = -log [OH⁻]
pOH = 4.31
Knowing pH = 14 - pOH
pH = 9.69
The pH of a 1.4 M pyridine solution is 9.69. When pyridine (C₅H₅N) is added to water, the equilibrium occurs. The rate of forward reaction is equals to the rate of backward reaction.
Equilibrium for pyridine:When pyridine (C₅H₅N) is added to water, the equilibrium that occurs is:
C₅H₅N(aq) + H₂O(l) ⇌ C₅H₅NH⁺(aq) + OH⁻(aq) Kb = 1.7x10⁻⁹
Where Kb is defined as:
Kb = 1.7x10⁻⁹
Kb= [C₅H₅NH⁺] [OH⁻] / [C₅H₅N]
If you have a solution of 1.4M C₅H₅N, the equilibrium concentration of each specie is:
[C₅H₅N] = 1.4 - x
[C₅H₅NH⁺] = x
[OH⁻] = x
Where x represents the reaction coordinate
Replacing in Kb expression:
1.7*10⁻⁹ = [x] [x] / [1.4 -x]
2.38*10⁻⁹ - 1.7x10⁻⁹x = x²
0 = x² + 1.7*10⁻⁹x - 2.38*10⁻⁹
Solving for x:
x = 0.0000488M
Thus, [OH⁻] = 0.0000488M.
As pOH = -log [OH⁻]
pOH = 4.31
Knowing pH = 14 - pOH
pH = 9.69
Find more information about Equilibrium constant here:
brainly.com/question/12858312
The periodic table of the elements lists the elements in order of increasing atomic number. Each element has its own unique square in the periodic table. Numbers in an element's square are used to tell how many protons, neutrons and electrons a typical atom of each element has.

Based on the information shown, which of the following is true about magnesium atoms?
A.
They all have 12 protons.
B.
Some have 24 protons and others do not.
C.
They all have 24 protons.
D.
Some have 12 protons and others do not.
Answer:
A) They all have 12 protons.
Explanation:
Magnesium has an atomic number of 12 which means it has 12 protons. All Magnesium atoms have 12 protons, the neutrons however may differ which produces things called isotopes where the atoms have same protons but neutrons change.
Keep in mind the atomic number is unique to each element, so 12 atomic number will always be Magnesium, 1 will always be Hydrogen and so on.....
which would dissolve faster individual salt crystals a big block of salt
Answer:
Table salt (the iodine isn't important) consists of much smaller particles than rock salt and therefore has a much higher ratio of surface area to mass. Since chemical reactions occur at surfaces,the smaller table salt particles will dissolve far more quickly than the larger rock salt.
Explanation:
Answer:
Individual salt crystals
Explanation:
A given quantity of solute dissolves faster when it is ground into small particles than if it is in the form of a large chunk because more surface area is exposed.
Give me a good review if right please.
A 125 g sample of strontium was heated from 0°C to 20°C. It absorbed 750 J of energy. What is the specific heat capacity of iron?
Answer:
Specific heat capacity of iron (C) = 0.3 J/GK
Explanation:
Given:
Mass of sample (m) = 125 gram
Change in heat (ΔT) = 20°C - 0°C = 20°C
Absorbed energy (ΔE) = 750 J
Find:
Specific heat capacity of iron (C) = ?
Computation:
⇒ Specific heat capacity of iron (C) = ΔE / [mΔT]
⇒ Specific heat capacity of iron (C) = 750 / [125 × 20]
⇒ Specific heat capacity of iron (C) = 750 / [2,500]
⇒ Specific heat capacity of iron (C) = 0.3 J/GK
Answer:
Specific heat capacity of iron (C) [tex]= 0.3[/tex] J/g°C
Explanation:
As we know that
Specific heat capacity of iron (C) [tex]=\frac{\delta E}{ [m* \delta T]}[/tex]
Where [tex]\delta E[/tex] represents the change in the energy
m represents the mass of the sample and
[tex]\delta T[/tex] represents the change in temperature.
Given:
Mass of sample (m) [tex]= 125[/tex] gram
Change in heat ([tex]\delta T[/tex] ) [tex]20 - 0 = 20[/tex]
Absorbed energy ([tex]\delta E[/tex])[tex]= 750[/tex] J
Substituting the given values in above equation, we get -
Specific heat capacity of iron (C)
[tex]= \frac{750}{125*20}[/tex]
Specific heat capacity of iron (C) [tex]= 0.3[/tex] J/g°C
Polyatomic ion formula for aluminum hydroxide
Answer:
Al(OH)3 ? i hope this is what you mean.
Answer:
The formula for aluminum hydroxide is Al(OH)3.
Explanation:
Typically, metal hydroxides form strong bases in solution. Aluminum hydroxide is special compound because it is amphoteric. This means it can react as a base or as an acid.
which of the folowing alkanes can exhibit optical acitivity?(A)2-methylbutane,(B)2,3-Dimethylbutane,(C)3-methylpentane,(D)cyclobutane
Answer:
B
Explanation:
hope my answer helps you
What is the poH of a
6.5 x 10-12 M OH solution?
pOH = [?]
Answer:
[tex]pOH=11.2[/tex]
Explanation:
Hello,
In this case, by knowing that the pOH is defined in terms of the concentration of OH⁻ as shown below:
[tex]pOH=-log([OH^-])[/tex]
We directly compute with the given concentration:
[tex]pOH=-log(6.5x10^{-12})\\\\pOH=11.2[/tex]
Moreover, fur such pOH, the pH will be:
[tex]pH=14-11.2=2.8[/tex]
Which means that such solution is an acid solution.
Best regards.
Answer:
11.2
Explanation:
Sometimes in lab we collect the gas formed by a chemical reaction over water (see sketch at right). This makes it easy to isolate and measure the amount of gas produced.
Suppose the CO gas evolved by a certain chemical reaction taking place at 55 degree C is collected over water, using an apparatus something like that in the sketch, and the final volume of gas in the collection tube is measured to be 117 ml.
Calculate the mass of CO that is in the collection tube. Round your answer to 2 significant digits. You can make any normal and reasonable assumption about the reaction conditions and the nature of the gases.
Answer:
The correct answer is 0.12 grams.
Explanation:
The mass of carbon monoxide or CO collected in the tube can be determined by using the ideal gas equation, that is, PV = nRT.
Based on the given question, P or the pressure of the gas is given as 1 atm, volume of the gas collected in the tube is 117 ml or 0.117 L.
The number of moles or n can be determined by using the equation, mass/molar mass.
R is the universal gas constant, whose value is 0.0821 L atmK^-1mol^-1, and temperature is 55 degree C or 328 K (55+273).
On putting the values we get:
n = PV/RT
= (1 atm*0.117 L) / (0.0821 L atmK^-1mol^-1 * 328 K)
= 0.0043447 mol
Therefore, mass of CO will be moles * molar mass of CO
= 0.0043447 mol * 28 g/mol
= 0.12 g
Nitrogen gas was collected by water displacement. What was the pressure of the N2 collected if the temperature was 50 degrees celcius?
Answer:
Explanation:
Atmospheric pressure = 101.325 kPa
vapor pressure of water at 50°C = 12.332 kPa
pressure of N₂ = (Atmospheric pressure) - (vapor pressure of water at 50 oC)
pressure of N₂ = (101.325 kPa) - (12.332 kPa)
pressure of N₂ = 88.993 kPa
Therefore, the pressure of the N₂ collected if the temperature was 50 degrees celcius is 88.993 kPaAscorbic acid (H2C6H6O6), also known as Vitamin C, is a polyprotic acid found in fruit, tomatoes, potatoes and leafy vegetables. The pKa's of the ascorbic acid are pKa1 = 4.10 and pKa2 = 11.80 at 25 °C. When ascorbic acid is titrated with NaOH and it takes 60.0 mL to remove all protons possible. In the titration curve, how many mL of NaOH are required to reach the first pKa? Another way of asking this is when presented with a titration curve of ascorbic acid where on the x-axis should one look (which volume of NaOH), if one wants to determine the first pKa?
Answer:
as when we add 60 ml it removes all the protons it means it is 2nd equivalence point of Ascorbic acid
and we know that pH = pKa1 when moles of NaOH is half of the 1st equivalence point
1st equivalence point = 2nd equivalence point / 2 = 60/2 =30ml
1st half equivalence point = 30/2 = 15ml
so when we add 15ml of NaOH
pH = pKa1 =15mL
What parts of the body are tested for rigor Mortis
What is the hydronium ion concentration of a 0.100 M acetic acid solution with Ka = 1.8 × 10-5? The equation for the dissociation of acetic acid is: CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq) What is the hydronium ion concentration of a 0.100 M acetic acid solution with Ka = 1.8 × 10-5? The equation for the dissociation of acetic acid is: CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq) 1.3 × 10-2 M 4.2 × 10-2 M 1.3 × 10-3 M 4.2 × 10-3 M
Answer:
1.3×10⁻³ M
Explanation:
Hello,
In this case, given the dissociation reaction of acetic acid:
[tex]CH_3CO_2H(aq) + H_2O(l) \rightleftharpoons H_3O^+(aq) + CH_3CO_2^-(aq)[/tex]
We can write the law of mass action for it:
[tex]Ka=\frac{[H_3O^+][CH_3CO_2^-]}{[CH_3CO_2H]}[/tex]
Of course, excluding the water as heterogeneous substances are not included. Then, in terms of the change [tex]x[/tex] due to the dissociation extent, we are able to rewrite it as shown below:
[tex]1.8x10^{-5}=\frac{x*x}{0.100-x}[/tex]
Thus, via the quadratic equation or solve, we obtain the following solutions:
[tex]x_1=-0.00135M\\x_2=0.00133M[/tex]
Obviously, the solution is 0.00133M which match with the hydronium concentration, thus, answer is: 1.3×10⁻³ M in scientific notation.
Regards.
Answer:
1.3×10^-3 M
Explanation:
Step 1:
Data obtained from the question:
Equilibrium constant (Ka) = 1.8×10^-5
Concentration of acetic acid, [CH3COOH] = 0.100 M
Concentration of hydronium ion, [H3O+] =..?
Step 2:
The balanced equation for the reaction.
CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq)
Step 3:
Determination of concentration of hydronium ion, [H3O+].
This can be obtained as follow:
Ka = [H3O+] [CH3CO2-] / [CH3CO2H]
Initial concentration:
[CH3COOH] = 0.100 M
[H3O+] = 0
[CH3CO2-] = 0
During reaction
[CH3COOH] = – y
[H3O+] = +y
[CH3CO2-] = +y
Equilibrium:
[CH3COOH] = 0.1 – y
[H3O+] = y
[CH3CO2-] = y
Ka = [H3O+] [CH3CO2-] / [CH3CO2H]
1.8×10^-5 = y × y / 0.1
Cross multiply
y^2 = 1.8×10^-5 x 0.1
Take the square root of both side
y = √(1.8×10^-5 x 0.1)
y = 1.3×10^-3 M
[H3O+] = y = 1.3×10^-3 M
Therefore, the concentration of the hydronium ion, [H3O+] is 1.3×10^-3 M
A reaction starts with 20.0 g of lithium hydroxide (LiOH) and actually produces 31.0 g of lithium chloride (LiCl), what is the percent yield? (Hint: First calculate the theoretical yield of lithium chloride (LiCl))
64.5%
88.6%
81.5%
92.8%
Answer:
87.6 %
Explanation:
Step 1: Write the balanced equation
LiOH + KCl ⇒ LiCl + KOH
Step 2: Calculate the theoretical yield of LiCl
We will use the following relations:
The molar mass of LiOH is 23.95 g/mol.The molar ratio of LiOH to LiCl is 1:1.The molar mass of LiCl is 42.39 g/mol.The theoretical yield of LiCl from 20.0 g of LiOH is:
[tex]20.0gLiOH \times \frac{1molLiOH}{23.95gLiOH} \times \frac{1molLiCl}{1molLiOH} \times \frac{42.39gLiCl}{1molLiCl} = 35.4gLiCl[/tex]
Step 3: Calculate the percent yield of LiCl.
We will use the following expression.
[tex]\%yield = \frac{real\ yield}{theoretical\ yield} \times 100\% = \frac{31.0g}{35.4g} \times 100\% = 87.6 \%[/tex]
Answer:
88.6%
Explanation:
Hello,
In this case, considering the given reaction, we notice a 1:1 molar relationship between lithium hydroxide (molar mass=23.95 g/mol) and lithium chloride (molar mass=42.394 g/mol), for that reason, we are able to compute the theoretical yield of lithium chloride by stoichiometry:
[tex]m_{LiCl}^{theoretical}=20.0gLiOH*\frac{1molLiOH}{23.95gLiOH}*\frac{1molLiCl}{1molLiOH} *\frac{42.394 gLiCl}{1molLiCl}=35.4gLiCl[/tex]
Next, by knowing the actual yield of 31.0 g, we compute the percent yield as:
[tex]Y=\frac{m_{LiCl}^{actual}}{m_{LiCl}^{theoretical}} *100\%=\frac{31.0g}{35.4g}*100\%\\ \\Y=87.6\%[/tex]
Therefore, among the given, the answer should be 88.6%
Best regards.
please help! BRAINLIEST to right answerrrr
Answer: from the hotter surface to the colder one
Explanation:
Answer:d
d
Explanation:
Plants remove carbon to the atmosphere during
Answer:
respiration
Explanation:
Plants give out carbon dioxide not only at night but during the day too. It happens because of the process of respiration in which plants take in oxygen and give out carbon dioxide. As soon as the sun rises another process called photosynthesis starts, in which carbon dioxide is taken in and oxygen is given out.
Plants use photosynthesis to capture carbon dioxide and then release half of it into the atmosphere through respiration. Plants also release oxygen into the atmosphere through photosynthesis
What is the total oxidation state of the fluorine atoms
Answer:
-1
Explanation:
Which shows an isomer of the molecule below?
Answer:
D
Explanation:
An isomer is a molecule with the same number of atoms as another compound, but they differ in arrangement of the atoms.
Answer:
D
Explanation:
A P E X
When is the small size of gas particles taken into account?
Answer:
At high pressures and low temperatures.
Explanation:
That's when the volume of the gas is quite small.
The volume of the gas particles can then be a significant proportion of the total volume.
What is the binding energy of a mole of nuclei with a mass defect of 0.00084 kg/mol?
Answer:
The binding energy of a mole of the nuclei is 252KJ
Explanation:
The binding energy is the amount of energy required to separate an atom into its nuclei.
From Einstein's relations,
E = Δm[tex]c^{2}[/tex]
where E is the energy, Δm is the mass defect and c is the speed.
The mole of nuclei moves with the speed of light, so that;
c = 3.0 × [tex]10^{8}[/tex] m/s
Given that Δm = 0.00084Kg/mol, the binding energy is calculated as;
E = 0.00084 × 3.0 × [tex]10^{8}[/tex]
= 252000
= 252KJ
The binding energy of a mole of the nuclei is 252KJ.
Answer:
7.55×10^10 KJmol-1
Explanation:
The actual mass of a nucleus is usually less than the sum of the masses of the constituent neutrons and protons that make up the nucleus. This difference is called the mass defect.
The mass defect is related to the binding energy holding the neutrons and protons together in the nucleus. Since energy and mass are related by Einstein's equation;
E=∆mc^2 where;
E = binding energy of the nucleus
∆m= mass defect of the nucleus
c= speed of light
The larger the mass defect, the larger the binding energy of the nucleus and the more stable the nucleus.
From the data provided;
Mass defect= 0.00084 kg/mol or 0.84g/mol
Since 1 g/mol= 1 amu
0.84g/mol= 0.84 amu
The conversion factor from atomic mass units to MeV is 931
Binding energy = 0.84 × 931= 782.04 MeV
Since 1eV= 96.49KJmol-1
782.04×10^6eV= 7.55×10^10 KJmol-1
How many grams of californium-254 will remain after 363 days if we
start with 64.0 grams of this substance? The half-life of californium-254
is 60.5 days.
Answer:
1.02 g OF CALIFORNIUM-254 WILL REMAIN AFTER 363 DAYS IF 64 g REACTS WITH HALF LIFE OF 60.5 DAYS.
Explanation:
Half life of a chemical reaction is the time required for a radioactive element to decay to half its original mass.
We will use the formula:
Nt = No (1/2)^t/t1/2 where;
Nt = quantity of substance remaining = unknown
No = original mass of the substance = 64 g
t = time elapsed = 363 days
t1/2 = half life of the substance = 60.5 days
Putting the values into the equation, we have:
Nt = 64 * (1/2)^(363/60.5)
Nt = 64 * (1/2) ^6
Nt = 64 * 0.015625
Nt = 1.0156
The amount of californium-254 remaining after 363 days is approximately 1.02 g
How are plastic containers different from paper containers? How are they the same?
Answer:
Paper is Not Reuseable like plastic.
Explanation:
The temperature of a 350. mL sample of gas increases from 27 °C to 227 °C. What is the final volume of the sample of gas, if the pressure and amount of gas in the container is kept constant?
Group of answer choices
Answer:
[tex]V_2=583.3mL[/tex]
Explanation:
Hello,
In this case, for the given constant amount and pressure of the, we apply the Charles' law which allows us to understand the volume-pressure behavior as a directly proportional relationship:
[tex]\frac{V_1}{T_1} =\frac{V_2}{T_2}[/tex]
Thus, since we need to compute the volume after the temperature increase (which must be expressed in absolute Kelvins), we obtain V2 as:
[tex]V_2=\frac{V_1T_2}{T_1} =\frac{350.0mL*(227+273.15)K}{(27+273.15)K}\\ \\V_2=583.3mL[/tex]
Best regards.
CH³C⁴HCOCH³ how many atoms of each element are in one molecule of 2-heptanone
Answer:
- 7 carbon atoms.
- 14 hydrogen atoms.
- 1 oxygen atom.
Explanation:
Hello,
In this case, for the given compound, heptanone, whose chemical formula is:
[tex]CH_3COCH_2CH_2CH_2CH_2CH_3[/tex]
We can write the molecular formula showing the present atoms of each element:
[tex]C_7H_{14}O[/tex]
In such a way we have:
- 7 carbon atoms.
- 14 hydrogen atoms.
- 1 oxygen atom.
Best regards.
The image shows two different species. the image is a dog and a lizered
Which is a shared characteristic of these two species?
tail
scales
hair
body shape
Answer:
the tail
Explanation:
Answer:
A.) tails
Explanation:
Living large means we use a lot of energy. What are three ways people use energy in their daily lives?
Answer:
right now we are using energy by online learning on our laptops , air conditioning, and transportation
Explanation:
After 56.0 min, 40.0% of a compound has decomposed. What is the half‑life of this reaction assuming first‑order kinetics?
Answer:
Go ahead and plug in the percentages and time to find the answer.
Explanation:
The amount of a substance with half-life h, that remains after time t is 0.5t/h
Since 26% has decomposed, 74% remains.
So .74 = 0.580/h
ln .74 = (80/h) ln 0.5
h/80 = ln 0.5 / ln .74
h = 80 ln 0.5 / ln .74
h = 184.16 minutes
Which characteristic of a substance is considered a chemical property
Answer:
c
Explanation:
3Fe + 2O2 → Fe3O4 In this reaction, 200 grams of Fe react with 64 grams of O2. How many grams of Fe3O4 will be produced? A 230 grams B 264 grams C 280 grams D 460 grams
Answer:
just did it the answers b
Explanation:
Which of the following 0.5 M aqueous salt solutions will have a pH of 7.0 at
LiF RbBr NaClO4 NH4Cl
A) LiF only B) NaClO4 only C) LiF and RbBr D) RbBr and NaClO4
Answer:
LiF and RbBr
Explanation:
Salt is an ionic compound that is made from the reaction of an acid and a base solution. Salts dissolve in water to give solutions that are acidic, basic, or neutral.
Salt formed from a strong acid and a weak base will make an acidic solution when added to water. The reason this occurs is because when the salt dissociates, the conjugate acid of the weak base will donate a proton, or one hydrogen ion, to water and form hydronium ion.
If a salt is formed from a weak acid and a strong base, it dissolves in water and the conjugate base of the weak acid will accept a proton from water and yield the hydroxide ion. Hence the solution of the salt will be basic.
If the salt is formed from a strong acid and a strong base, the salt is neutral when dissolved in water. Both LiF and RbBr are formed from strong acids and strong bases hence they will have a pH of 7.0 in solution.
LiF RbBr NaClO4 NH4Cl is = LiF and RbBr The correction is 'C'.
What are the Salt solutions?
Salt is an ionic mixture that is made from the reaction of an acid and a base resolution. Salts liquefy in water to give solutions that are acidic, basic, or neutral.
Salt constructed from a strong acid and a breakable base will make an acidic solution when added to water. The reason this occurs is that when the salt dissociates, the conjugate acid of the weak base will donate a proton, or one hydrogen ion, to water and form a hydronium ion.
If a grain of salt is formed from a weak acid and a powerful ground, it liquefies in water and the conjugate bottom of the weak acid will accept a proton from water and yield the hydroxide ion. Therefore, the solution of the salt will be basic.
If the salt is formed from a strong acid and a strong bottom, the salt is neutral when liquefied in water. Both LiF and also RbBr are formed from strong acids and powerful bases hence they will have a pH of 7.0 in resolution.
Therefore, the Correct option is 'C'
Find more information about Salt solutions here:
https://brainly.com/question/24856349
