Assume Raoult's Law applies to a binary mixture of water and methanol at 70 C.
a) Which species should be considered species (a)? Why?
b) Prepare a Pxy diagram for this mixture
c) What is the composition of the vapor in equilibrium with liquid at xi for methanol of 0.3?
d) What is the composition of the liquid in equilibrium with vapor at yi for water of 0.3?
For parts (c) and (d), determine these composition values analytically. Then confirm that they are correct on the Pxy diagram you created in part (b).
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To a 100.0 mL volumetric flask were added 7.00 mL of 1.70 M of H3VO4, 1.401 g of NaH2VO4, and 15.00 mL of 1.5 M NaOH. The flask was filled to the calibration mark with water. What were the molar concentrations of H+, OH-, the two other relevant molecules and the pH of the solution? Is the resulting solution a buffer? Ka1 = 1.0 x 10-4, Ka2 = 2.8 x 10-9 and Ka3 = 5.0 x 10-15 for H3VO4.
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Calculate the pH of a 0.800 M NaCH3CO2 solution. Ka for acetic acid, CH3CO2H, is 1.8 × 10-5. If someone could list the steps and calculations that would be helpful. Thank you!
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Denaturation can occur if a protein is heated or undergoes changes in pH. Denaturation disrupts the secondary, tertiary, and quaternary structure of a protein. Would you expect the Biuret test to work on a protein that had been denatured? Why or why not?
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(a) How many grams of CaCl2 are needed to make 798.0 g of a solution that is 32.5% (m/m) calcium chloride in water? Note that mass is not technically the same thing as weight, but (m/m) has the same meaning as (w/w).
-How many grams of water are needed to make this solution?
(b) What is the volume percent % (v/v) of an alcohol solution made by dissolving 147 mL of isopropyl alcohol in 731 mL of water? (Assume that volumes are additive.)
(c) The mass of solute per 100 mL of solution is abbreviated as % (m/v). (The abbreviation % (w/v) is also common.) How many grams of sucrose are needed to make 915 mL of a 38.0% (w/v) sucrose solution?
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50.0mL of .500M NaOH is added to 25.0mL of .500M HCL in a calorimeter BOth are at an initial temperature of 25 C ans final temperature is 27.21 C. Assume the mass of the final solution is 76.0 g and the Cs of the solution is 4.18 J/gC. what is the value of q for water, what is the value of q for the reaction, what is the change of H of the reaction in kj/mol?
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What would be the effect of each of the following on the calculated molar mass of the solute?
1. some cyclohexane evaporated while the freezing point of pure cyclohexane was being measured.
2. some cyclohexane evaporated after the solute was added.
3. some unknown power was still left one the weighing paper.
4. a foreign solute was already present in the cyclohexane?
5. the thermometer is not calibrated correctly. it gives a temperature that is 1.5 C too low at all temperatures.
6. solution didn't freeze completely.
please help me answer these. thank you! i promise to rate you :)
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BCl3is a monomer that is a gas at room temperature while the analogous Al compound is the Al2Cl2 dimer with 2 chlorides bridging between the two Al's. Draw Lewis structures of each compound and suggest a reason for the significant differences in the strucutres. Note that it is important that Al and B obey the ocetet rule in your Lewis strucutures.
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13) Calculate the change in pH when 8.00 mL of 0.100 M HCl(aq) is added to 100.0 mL of a buffer solution that is 0.100 M in NH3(aq) and 0.100 M in NH4Cl(aq).
delta pH=?
Calculate the change in pH when 8.00 mL of 0.100 M NaOH(aq) is added to the original buffer solution.
delta pH=?
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What is the pH of a solution that results when 0.012 mol HNO3 is added to 610.0 mL of a solution that is 0.26 M in aqueous ammonia and 0.46M in ammonium nitrate. Assume no volume change. (Kb for NH3 = 1.8 × 10–5.)
a. 8.96
b. 9.56
c. 5.04
d. 9.01
e. 4.44
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When a cell reaction reaches equilibrium, E = 0. E = 0. both E and E = 0. neither E nor E = 0.
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Calculate analytical concentration for each of the following solutions:
a) HCl solution, pH = 1.34
b) Acetic acid solution, pH = 4.31
c) Sulfuric acid solution, pH = 2.21
d) Potassium hydroxide solution, pH = 12.21
Acetic acid: pKa = 4.76
Sulfuric acid: pKa,1 = strong, pKa,2 = 1.99
In water, [H3O+][OH–] = 1.00 ! 10–14
Ignore the effect of ionic strength.
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g. Which of the above compounds are ionic? Which are molecular?
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Calculate [H3O+] and [OH−] for each of the follo...
pH= 8.56
pH= 11.20
pH= 2.84
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A.
Calculate [H3O+] in the following aqueous solution at 25 ?C: [OH?]= 1.6×10?9 M .
Express your answer using two significant figures.
B.
Calculate [H3O+] in the following aqueous solution at 25 ?C: [OH?]= 3.0×10?2 M .
Express your answer using two significant figures.
C.
Calculate [H3O+] in the following aqueous solution at 25 ?C: [OH?]= 7.0×10?12 M .
Express your answer using two significant figures.
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