ACIDS BASES AND BUFFERS - PHYSICAL 2

Question 1

whats an acid

Answer 1

substance that can donate a proton (H+)

Question 2

whats a base

Answer 2

substance that can accept a proton

Question 3

What is a buffer?

Answer 3

a substance that can resist the change in pH when a small amount of acid or alkali is added to it

Question 4

What is a brønsted-lowry base?

Answer 4

a proton acceptor

Question 5

What is a brønsted-lowry acid?

Answer 5

proton donor

Question 6

What is a weak acid?

Answer 6

a proton donor that partially dissociates in water

Question 7

What is a strong acid?

Answer 7

a proton donor that fully dissociates in water

Question 8

What is the equation for pH?

Answer 8

pH = -log[H+]

Question 9

Why is the pure water always neutral, regardless of pH?

Answer 9

[H+] = [OH-]

Question 10

equation for the reaction of a strong acid with water

Answer 10

HA + H2O –> H3O+ + A-

Question 11

equation for the reaction of a weak acid with water

Answer 11

HA + H2O <–> H3O+ + A-

Question 12

equation for the ionic product of water (Kw)

Answer 12

Kw = [H+] [OH-]

Question 13

modify Kw, in order to calculate the pH of pure water?

Answer 13

Kw = [H+]^2

Question 14

How do you calculate pKa?

Answer 14

-log Ka

Question 15

calculate Ka from pKa?

Answer 15

10^-pKa

Question 16

expression for Ka?

Answer 16

[H+][OH-] / [HA]

Question 17

modified Ka for doing buffer calculations?

Answer 17

Ka = [H+] x (salt / acid)