Test yourself : Chemistry Form 4
Chapter 7 : Acid and Bases
Section 1
A.
Acid and Bases
1. Complete the general equations below.
2.
a. Acid + alkali
 ___________________________________________
b. Acid + reactive metal
 ___________________________________________
c. Acid + metal carbonate
 ___________________________________________
d. Acid + metal oxide
 ___________________________________________
e. Alkali + ammonium salt
 ______________________________________________
Based on question 1, complete the chemical equation below.
a. HCl + NaOH
 ________________________________________________
b. H2SO4 + Mg
 ________________________________________________
c. 2HNO3 + ZnCO3
 ________________________________________________
d. H2SO4 + CuO
 ________________________________________________
e.
NaOH + NH4Cl
 ________________________________________________
B. Concentration of Acid and Bases
1. Calculate the concentration in g mol-1 of 0.5 mole potassium hydroxide in 5.0 dm3
solution.
[Relative atomic mass; H.1;K.39;O,16]
2. Find the concentration of 2.0 mol dm-3 sodium chloride solution in g dm-3
[Relative atomic mass : Cl, 35.5; Na, 23]
3. 4.0 g of sodium, hydroxide is dissolved in water to make up 500 cm 3 of solution.
Calculation the molarity of sodium hydroxide solution obtained.
[ Relative atomic mass : H,1; Na, 23; O,16]
4. Calculate the number of moles of copper (II) sulphate in 250 cm 3 of 1.5 mol dm-3
copper (II) sulphate solution.
5. What is the volume of 2.0 mol dm-3 sodium chloride solution needed to prepare 250
cm3 of 0.2 mol dm-3sodium chloride solution?
C. Neutralisation
1. What is the volume of 0.2 mol dm-3 hydrochloric acid needed to neutralize 25 cm3 of
1.0 mol dm-3 potassium hydroxide solution?
2. What is the mass of zinc oxide needed to neutralize 50 cm3 of 0.5 mol dm-3 sulphuric
acid?
[ Relative atomic mass: Zn, 165; O,16]
3. What is the molarity of 25 cm3of sodium hydroxide solution that is needed to neutralize
10 cm3 of 0.2 mol dm-3 sulphuric acid?
Section 2
1
The table below shows the description and observation for two experiments involving two
solutions:


Hydrogen chloride in solvent X
Hydrogen chloride in solvent Y
Experiment
(a)
Description
Observation
HCl in solvent X
HCl in solvent Y
I
Reaction of hydrogen
chloride in solvent X and
solvent Y with calcium
carbonate lumps.
Effervescence
occurs. A colourless
gas is liberated.
No change occur
II
Electrolysis of hydrogen
chloride in solvent X and
solvent Y
Ammeter shows
reading
Ammeter does not
show reading.
Name a suitable compound for
Solvent X : .............................................................................................................
Solvent Y: ................................................................................................................
[2 marks]
(b)
(i)
Which of the solution shows acidic properties?
....................................................................................................................
(ii)
What is the role of solvent in (b) (i) that enables the solution to show
acidic properties?
....................................................................................................................
[2 marks]
(c)
(i)
Effervescence occurs when hydrogen chloride in solvent X react with
calcium carbonate. Name the gas liberated.
...................................................................................................................
(ii)
Describe a chemical test to identify the gas liberated in (c) (i)
....................................................................................................................
....................................................................................................................
(iii)
Write ionic equation for the reaction in (c) (i).
....................................................................................................................
[4 marks]
(d)
Hydrogen chloride in solvent X can conduct electricity but hydrogen chloride in
solvent Y cannot conduct electricity. Explain why.
....................................................................................................................
....................................................................................................................
[2 marks]
(e)
Calculate the mass of hydrogen chloride gas, HCl to prepare 100 cm3 of 0.5 mol
dm-3 HCl acid.
[Given that the relative atomic mass of H = 1, Cl = 35.5 , C = 12, Ca = 40 , O =
16 ]
[3 marks]
2 The diagram shows the set up apparatus for the titration of sodium hydroxide solution with
hydrochloric acid.
Hydrochloric acid
1moldm-3
50 cm3 of 1 moldm-3
sodium hydroxide
solution and
phenolphthalein
1.0 moldm-3 hydrochloric acid is added to 25 cm3 of 1.0 moldm-3 sodium hydroxide solution and
phenolphthalein is used as an indicator .
a)
(i) Name the reaction between sodium hydroxide solution and hydrochloric acid.
………………………………………………………………………………………………………
[ 1 mark ]
(ii) Name the salt produced in the experiment.
(b)
………………………………………………………………………………………………………
[ 1 mark ]
State the colour change in the conical flask at the end point.
(c)
………………………………………………………………………………………………………
[ 1 mark]
Write a chemical equation for the reaction occurs in the conical flask.
………………………………………………………………………………………………………
[ 1 mark]
(d)
(i) Calculate the volume of 1.0 moldm-3 hydrochloric acid needed to exactly neutralise
25 cm3 of 1.0
moldm-3 sodium hydroxide solution.
[2 marks ]
(ii) The experiment above is repeated by replacing 1.0 moldm-3 hydrochloric acid with
0.5 moldm-3 sulphuric acid. Predict the volume of
sulphuric acid required to
complete neutralise the sodium hydroxide solution.
…………………………………………………………………………………………………
[ 2 marks ]
(e)
Calculate the maximum mass of the salt formed in this experiment.
[Given that the relative atomic mass of Na = 23, Cl = 35.5 ]
[ 2 marks ]
(f) State one of the uses of the salt formed in daily lives.
……………………………………………………………………………………………………….
[ 1 mark ]