Q.1
Which of the following is an endothermic reaction?
  • HCI + NaOH → NaCl + H2O
  • HCI + NaHCO3 → NaCl + CO2 + H2O
  • NaCl + AgNO3 → AgCl + NaNO3
  • Zn + CuSO4 → ZnSO4 + Cu
Q.2
The following equation shows the combustion of heptane, C7Hin excess oxgen.C7H16(l) +O2(g) → 7 CO2(g) + 8 HΔH= -5kJ mol-The combustion of heptane in excess oxygen releases 1kJ of energy.What is the mass of heptane used?[relative atomic mass of H = 1 and C = 12]
  • 25.0 g
  • 36.0 g
  • 77.0 g
  • 88.0 g
Q.3
The following information shows the results of an experiment to determine the heat change for the combustion of propanol, C3H7OH.Volume of water in the copper container=cm3Initial temperature of water in copper container=27.5 °CHighest temperature of water in copper container = 68.5 °CWhat is the heat released by the combustion of propanol, C3H7OH? [Specific heat capacity of water = 4.2 J g-1°C-1 ; Water density = 1 g cm-3]
  • 34.65 kJ
  • 51.66 kJ
  • 86.3 kJ
  • 120.96 kJ
Q.4
What is precipitation reaction?
  • Two different aqueous soluble salts are mixed to form a soluble salt.
  • Two different aqueous soluble salts are mixed to form an insoluble salt.
  • Two different aqueous soluble salts are mixed to form an insoluble salt and a soluble salt.
  • One aqueous soluble salts are mixed with one insoluble salt to form an insoluble salt.
Q.5
Why is a polystyrene cup used in the experiment to determine the heat of reaction involving two aqueous solution?
  • To allow the temperature of the reaction to increase uniformly
  • So that the reaction takes place completely
  • To reduce the heat loss to the surrounding
  • To increase the quantity of heat loss to the surrounding
Q.6
Which of the following pairs of solutions has the same heat of precipitation as the reaction between lead (II) nitrate and hydrochloric acid?
  • Barium chloride and sodium sulphate
  • Calcium chloride and sodium carbonate
  • ammonium chloride and silver nitrate
  • copper (II) chloride and lead (II) nitrate
Q.7
A chemical reaction that absorbs heat from the surroundings is said to be __________ and has a __________ ΔH at constant pressure.
  • endothermic; positive
  • endothermic; negative
  • exothermic; negative
  • exothermic; positive
Q.8
ConvertkJ into joules
  • 0.042 J
  • 4200 J
  • 42000 J
  • 420 J
Q.9
What sort of reaction happens when an acid and an alkali are mixed?
  • Neutralisation
  • Combination
  • Acidifying
  • Displacement
Q.10
What is the formula for calculating heat?
  • H = ΔH x n
  • H = ΔH x mass
  • products - reactants
  • H = mc θ
Q.11
Neutralisation reactions
  • endothermic
  • exothermic
Q.12
In an experiment, 2 g of magnesium powder are added tocm3 of 0.2 mol dm–3 zinc sulphate solution. The temperature of the mixture increases by 12°C. What is the heat of displacement in this experiment?[Spesific heat capacity of a solution = 4.2 Jg–1 °C–Relative atomic mass of Mg = 24]
  • – 50.4 kJ mol-1
  • – 100 kJ mol-1
  • – 252 kJ mol-1
  • – 340 kJ mol-1
Q.13
In an exothermic reaction, heat is ...
  • taken in
  • given out
Q.14
The ______________is required to break the bonds of the reactants.
  • Carbonic energy
  • Activation energy
  • Plutonic energy
  • Energi Gaib
Q.15
Check only the FALCE statements:
  • The heat change at the end of a chemical reaction under constant pressure is called the bond energy.
  • Melting of salt is an exothermic process.
  • Freezing is an endothermic process.
  • All of above
Q.16
Check only the TRUE statements:
  • In endothermic reaction, the total energy of products is bigger than that of reactants.
  • Melting is an endothermic process.
  • Sublimation is the physical process when solid turns to gas.
  • All of above
Q.17
Which one of the following reaction(s) are (is) exothermic?
  • combustion of gases
  • Freezing of water
  • Melting of salt
  • Both A & B
Q.18
Which one of the following reactions are endothermic?
  • Fe(s)→Fe(l)
  • 2C+2H2+20kcal/mol → C2H
  • Ba(OH)2+CO2 → BaCO3+H2O+heat
  • Both A & B
Q.19
In a chemical reaction, energy is used to :
  • cause a change of state
  • overcome intermolecular forces
  • break or form bonds within molecules
  • All of above
Q.20
A change in matter in which heat is absorbed is ..... process
  • Endothermic
  • Exothermic
  • Absorbed
  • Gained
0 h : 0 m : 1 s