Question

A certain weak acid, HA , has a Ka value of 6.6×10−7. Part A Calculate the...

A certain weak acid, HA , has a Ka value of 6.6×10−7.

Part A

Calculate the percent ionization of HA in a 0.10 M solution.

Express your answer to two significant figures and include the appropriate units.

Part B

Calculate the percent ionization of HA in a 0.010 M solution.

Express your answer to two significant figures, and include the appropriate units.

Homework Answers

Answer #1

A)

HA dissociates as:

HA -----> H+ + A-

0.1 0 0

0.1-x x x

Ka = [H+][A-]/[HA]

Ka = x*x/(c-x)

Assuming x can be ignored as compared to c

So, above expression becomes

Ka = x*x/(c)

so, x = sqrt (Ka*c)

x = sqrt ((6.6*10^-7)*0.1) = 2.569*10^-4

since c is much greater than x, our assumption is correct

so, x = 2.569*10^-4 M

% dissociation = (x*100)/c

= 2.569*10^-4*100/0.1

= 0.257 %

Answer: 0.26 %

B)

HA dissociates as:

HA -----> H+ + A-

1*10^-2 0 0

1*10^-2-x x x

Ka = [H+][A-]/[HA]

Ka = x*x/(c-x)

Assuming x can be ignored as compared to c

So, above expression becomes

Ka = x*x/(c)

so, x = sqrt (Ka*c)

x = sqrt ((6.6*10^-7)*1*10^-2) = 8.124*10^-5

since c is much greater than x, our assumption is correct

so, x = 8.124*10^-5 M

% dissociation = (x*100)/c

= 8.124*10^-5*100/0.01

= 0.812 %

Answer: 0.81 %

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A certain weak acid, HA, has a Ka value of 7.4×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 7.4×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Express your answer to two significant figures and include the appropriate units. Part B Calculate the percent ionization of HA in a 0.010 M solution. Express your answer to two significant figures, and include the appropriate units.
A certain weak acid, HA, has a Ka value of 3.5×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 3.5×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Express your answer to two significant figures and include the appropriate units. Part B Calculate the percent ionization of HA in a 0.010 M solution. Express your answer to two significant figures, and include the appropriate units.
A certain weak acid, HA, has a Ka value of 1.4×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 1.4×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Express your answer to two significant figures and include the appropriate units. Part B is calculate the percent ionization of HA in a 0.010 M solution.
A certain weak acid, HA, has a Ka value of 1.6×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 1.6×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Express your answer as a percent using two significant figures. Part B Calculate the percent ionization of HA in a 0.010 M solution. Express your answer as a percent using two significant figures.
A certain weak acid, HA, has a Ka value of 6.9×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 6.9×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Express your answer as a percent using two significant figures. Part B Calculate the percent ionization of HA in a 0.010 M solution. Express your answer as a percent using two significant figures.
A certain weak acid, HA, has a Ka value of 6.9x10-7 1) Calculate the percent ionization...
A certain weak acid, HA, has a Ka value of 6.9x10-7 1) Calculate the percent ionization of HA in a 0.10 M solution Express your answer to two significant figures and include the appropriate units. Value = Units = 2) Calculate the percent ionization of HA in a 0.010 M solution Value = Units =
A certain weak acid, HA, has a Ka value of 4.3×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 4.3×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Part B Calculate the percent ionization of HA in a 0.010 M solution.
A certain weak acid, HA, has a Ka value of 5.5×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 5.5×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Part B Calculate the percent ionization of HA in a 0.010 M solution.
A certain weak acid, HA, has a Ka value of 9.4×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 9.4×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Part B Calculate the percent ionization of HA in a 0.010 M solution.
A certain weak acid, HA, has a Ka value of 5.7×10−7. Part A Calculate the percent...
A certain weak acid, HA, has a Ka value of 5.7×10−7. Part A Calculate the percent ionization of HA in a 0.10 M solution.Calculate the percent ionization of HA in a 0.010 M solution.