Acids and Bases

Question 1

What is a Bronsted-Lowry acid defined as?

Answer 1

a proton donor

Question 2

What is a Bronsted-Lowry base defined as?

Answer 2

a proton acceptor

Question 3

what is the product of the reaction between an Acid and a base

Answer 3

Salt + Water

Question 4

how can we determine the concentration of an acid or a basse

Answer 4

titration

Question 5

what is the name of the reaction between acid and base

Answer 5

neutralisation reaction

Question 6

what is the pH of an acid

Answer 6

pH<7

Question 7

what is the pH of a base

Answer 7

pH>7

Question 8

what are alkalis

Answer 8

bases that are soluble in water

Question 9

what does an acid-base equilibria involve

Answer 9

the transfer of protons

Question 10

what is a strong acid?

Answer 10

when they dissolve in water
it competely dissociates into ions. (protons)

Question 11

what is a weak acid?

Answer 11

when they dissolve in water
it slightly dissociates into ions

Question 12

what is produced when acids disscoiate

Answer 12

protons

Question 13

what is produced when bases dissociates

Answer 13

hydroxides

Question 14

what is defined as a strong base

Answer 14

it completley dissociates into OH-
(hydroxides)

Question 15

what is defined as a weak base

Answer 15

it slightly dissociates to hydroxide ions

Question 16

how do we calculate the pH

Answer 16

pH = - log [H+]

Question 17

what happens when we increase the concentration of an acid

Answer 17

it increases the acidity
pH decreases

Question 17

why does the pH decrease when we increase the concentration

Answer 17

more H+ is produced
concentration increases
when the acid dissociates

Question 18

what happens to the pH when we dilute an acid with wateer

Answer 18

increase in pH

Question 19

what happens to the concentration of the acid when its diluted by water

Answer 19

concentration decreases

Question 20

what happens to the [H+] when we dilute an acid in water

Answer 20

[H+] decreases

Question 21

what happens to the pH when we add a solid base to an acid solution

Answer 21

it will increase

Question 22

what happens to the volume of the solution when we add a solid base to the acid solution

Answer 22

volume stays the same

Question 23

what does the pH scale measure?

Answer 23

the [H+] in a solution

Question 24

what does a high [H+] suggest

Answer 24

more hydrogen ions lower pH

Question 24

what does a low [H+] suggest

Answer 24

less hydrogen ions higher pH

Question 25

what can water slightly dissociate into

Answer 25

H+ OH-

Question 26

what is the equation when water slightly dissociates

Answer 26

H2O -> H+ + OH-

Question 27

what type of reaction is the slight dissociation of water

Answer 27

endothermic reaction

Question 28

what does the reaction of the dissociation of water reach

Answer 28

dynamic equilibrium

Question 29

where is kw derived from

Answer 29

from the Kc of the dissociation of water

Question 29

what is the pH of water at room temperature

Answer 29

7

Question 30

what is the kw expression

Answer 30

Kw = [H+](aq) ][OH-(aq) ]

Question 31

why is pure water neutral

Answer 31

[H+](aq) = [OH-](aq)

Question 32

what happens to Kw when we increase the temperature?

Answer 32

the temperature increases

Question 33

why does the value of kw increase when we increase the temperature?

Answer 33

when temperature increases the equilibrium will move to the right. (cause the dissociation of water is endothermic) therefore more products are formed (OH- & H+)

Question 34

what are the units for Kw

Answer 34

mol2 dm-6

Question 35

what is the value for Kw at room temperature? 298K + 25 degrees

Answer 35

1.00 x 10-14 mol2 dm-6

Question 36

Explain why the expression for Kw does not include the concentration of water. (2 marks)

Answer 36

the concentration of water is really high concentration of water is constant

Question 37

Explain why the value of Kw increases as the temperature increases? (2 marks)

Answer 37

1. Dissociation is endothermic 2. Equilibrium moves to the right to oppose the increase in temperature. 9counteract change)