Determine which of the following solutions would be basic at 25 °C?
Kw = 1.0 × 10−14 mol2 dm-6
[H+] = 1.0 × 10−2 mol dm−3
[OH−] = 1.0 × 10−12 mol dm−3
solution of pH = 5.00
[H3O+] = 1.0 × 10−12 mol dm−3
Question 2
Marks: 1
Calculate the pH of a solution of NaOH of concentration 0.001 mol dm-3
1
3
11
13
Question 3
Marks: 1
Carbon dioxide reacts with water to form carbonic acid which can be represented in the following equation
CO2(g) + H2O(l) ⇋ H+(aq) + HCO3−(aq)
If the pressure is raised, what will happen to the position of equilibrium and the pH?
The equilibrium shifts to the right and pH increases
The equilibrium shifts to the right and pH decreases
The equilibrium shifts to the left and pH increases
The equilibrium shifts to the left and pH decreases
Question 4
Marks: 1
When comparing the separate reactions of 0.5 g magnesium metal with equal volumes and concentrations of hydrochloric acid and ethanoic acid you can say that the
Hydrochloric acid reacts faster than ethanoic acid as its pH is higher
More gas is produced with hydrochloric acid than with ethanoic acid
An equal volume of gas is produced with both hydrochloric acid and ethanoic acid.
Ethanoic acid reacts more slowly than hydrochloric acid because its pH is lower
Question 5
Marks: 1
A beaker contains 50 cm3 of sodium hydroxide solution and its pH is measured as 11. If 450 cm3 of water is added to the beaker, what will be the new pH of the solution?
3
9
10
11
Question 6
Marks: 1
In the table below are the formulae of some acids and bases. Which row shows only weak acids and weak bases?
A
CH3NH2
Ba(OH)2
HCOOH
B
CH3CH2COOH
C6H5NH2
HCOOH
C
NH3
HNO3
CH3CH2COOH
D
NH3
KOH
H2CO3
Question 7
Marks: 1
Three solutions of hydrochloric acid of different concentrations are shown below
X.0.100 mol dm-3
Y.0.001 mol dm-3
Z.0.010 mol dm-3
If these solutions are arranged from lowest to highest pH, then the order is
X﹤ Y ﹤ Z
X﹤ Z ﹤ Y
Y﹤ X ﹤Z
Y﹤ Z ﹤ X
Question 8
Marks: 1
Which of the following statements is correct?
As temperature increases, the pH value of pure water decreases
As temperature decreases, the pH value of pure water decreases
The pH of water is unaffected by temperature
Pure water is not neutral
Question 9
Marks: 1
Which row shows the correct properties of 0.1 mol dm-3 LiOH?
pH
Electrical conductivity
Universal indicator colour
A
10
poor
green
B
13
good
purple
C
10
poor
red
D
13
poor
blue
Question 10
Marks: 1
Equal volumes of hydrochloric acid of different concentrations are added to four beakers, A, B, C and D. Equal volumes of 1.0 mol dm-3 sodium hydroxide are then added to the beakers and the pH is measured.
Beaker
A
B
C
D
pH
1
5
7
13
Which beaker contains the most concentrated solution of hydrochloric acid?
