pH and [H+(aq)]

Question 1

what is the equation to find the pH?

Answer 1

pH = -log(10)[H+(aq)]

Question 2

at what temperature is pH true at?

Answer 2

298K

Question 3

how many decimal points should pH calculations be to?

Answer 3

2 decimal places

Question 4

what does the pH calculation give if there is a strong acid?

Answer 4

lower than 1

Question 5

what does the pH calculation give if there is a strong alkali?

Answer 5

higher than 14

Question 6

what does a low value of [H+(aq)] match?

Answer 6

a high value of pH
so more alkali

Question 7

what does a high value of [H+(aq)] match?

Answer 7

a low value of pH
so more acidic

Question 8

what is the equation to calculate the [H+(aq)]?

Answer 8

[H+(aq)] = 10 to the power of -pH

Question 9

A solution of hydrochloric acid has a hydrogen ion concentration of 0.010moldm-3.
What is the pH of the solution?

Answer 9

2.00

Question 10

A solution of nitric acid has a pH of 1.52.
What is the hydrogen ion concentration of the solution?

Answer 10

3.0x10-2 moldm-3

Question 11

how do you calculate the pH of strong monobasic acids?

Answer 11

• each molecule of an acid releases one proton when it dissociates
• so concentration of H+ is the same as the acid concentration

Question 12

how do you calculate the pH of strong dibasic acids?

Answer 12

• each molecule of an acid releases two protons when it dissociates
• so concentration of H+ is the double as the acid concentration
  e.g.
  [H+] = 2 x [H2SO4]

Question 13

how do you calculate the pH of strong tribasic acids?

Answer 13

• each molecule of an acid releases three protons when it dissociates
• so concentration of H+ is the triple as the acid concentration
  e.g.
  [H+] = 3 x [HNO3]

Question 14

how do you calculate the pH of strong tribasic acids?

Answer 14

• each molecule of an acid releases three protons when it dissociates
• so concentration of H+ is the triple as the acid concentration
  e.g.
  [H+] = 3 x [HNO3]