Calculate the quantity of electricity passed when 0.4 A flows for 1 hour 20 minutes through an electrolytic cell
- A. 4800C
- B. 3840 C
- C. 1920 C
- D. 32 C
Oxidation takes place at the anode during electrolysis because the anode
- A. is deficient in electrons
- B. is deficient in protons
- C. has excess electrons
- D. has attraction for positive ions
In dry Leclanche cell, manganese (IV) oxide acts as
- A. a reducing agent
- B. binding agent
- C. catalyst
- D. depolarizer
Consider the equilibrium reaction represented by the equation: 2SO2(g) + O2(g) ⇌ 2SO3(g) ∆H = – 197 kJmol-1. At equilibrium, increase in the total pressure of the system brings about
- A. decrease in rate of the reaction of the system
- B. decrease in temperature of the system
- C. increase in temperature of SO3
- D. increase in concentration of SO2
The high solubility of ethanol in water is due to its
- A. low boiling point
- B. low freezing point
- C. covalent nature
- D. hydrogen bonding
When 100 cm3 of a saturated solution of KCIO3 at 40oC is evaporated, 14 g of the salt is recovered what is the solubility of KCIO3 at 40oC? [KCIO3 = 122.5]
- A. 11.42 mol dm-3
- B. 8.80 mol dm-3
- C. 1. 14 mol dm-3
- D. 0.88 mol dm-3
Consider the reaction represented by the question below: KOH(aq) + HCI(aq) → KCI(aq) + H2O(l) What volume of 0.25 mol dm-3 KOH would be required to completely neutralize 40 cm3 of 0.10 mol dm -3 HCI?
- A. 40 cm3
- B. 32cm3
- C. 24cm3
- D. 16cm3
Which of the following compounds would dissolved in water to give a solution whose pH is less than 7?
- A. AI(NO3)3
- B. KNO3
- C. N2O
- D. NH3
An aqueous solution of CaCI2 is
- A. acidic solution
- B. alkaline solution
- C. a buffer solution
- D. a neutral solution
The colour of phenolphthalein indicator in dilute HNO
- A. colourless
- B. orange
- C. pink
- D. purple
Which of the following set of equations could be used to represent the standard enthalpy of formation of glucose?
- A. 6C (s) + 6H 2(g) + 3O2(g) → C 6H12O6(s)
- B. 6CO2(g) + 6H2O (l) → C6H12O6(s) + 6O 2(g)
- C. 6C(g) + 6H 2(g) + 3O2(g) → C6H12O 6(s)
- D. 6C(g) + 6H 2(g) + 3O2(g) → C 6H 12O 6(aq)
Diamond does not conduct electricity because it?
- A. has no free valence electrons
- B. is a giant molecule
- C. contains no bonded electrons
- D. is a solid at room temperature
The collision theory proposes that
- A. reactants collide more frequently to bring about reduction in the reaction rate
- B. all collisions of reactants are effective
- C. reactants must collide with a certain minimum amount of energy to from products
- D. the fewer the collisions the faster the reaction rate
When concentrated \(H_2SO_4\) is added to NaCI (s), the gas evolved
- A. bleaches damp blue litmus paper
- B. forms a white preciptate with AgNO3(aq)
- C. forms a white precipitate with BaCI2(aq)
- D. turns moist red litmus paper blue
In a fixed volume of a gas, an increase in temperature results in an increase in pressure due to an increase in the
- A. number of the collisions between the gas molecules and the walls of the container
- B. kinetic energy of the gas
- C. number of collisions between the gas molecules
- D. number of repulsion between the gas molecules
Which of the following gases has the lowerst rate of diffusion under the same conditions of temperature and pressure? [H = 1, O = 16, Ne = 20, CI = 35]
- A. Chlorine
- B. Hydrogen
- C. Neon
- D. Oxygen
Consider the reaction represented by the following equation: Zn(s) + 2HCI(aq) → ZnCI2(aq) + H2(g) what volume of hydrogen gas is produced at s.t.p. when 3.25 g of zinc reacts with excess dilute HCI? [Zn = 65, Molar gas volume at s.t.p. = 22.4 dm-3]
- A. 1.12 dm3
- B. 2.24dm3
- C. 4.48dm3
- D. 8.96dm3
If 5.00cm3 of 0.20 mol dm-3Na2CO3 was diluted with distilled water to obtain 250 cm3 solution, what is the concentration of the resulting solution?
- A. 0.004 mol dm-3
- B. 0.02 mol dm-3
- C. 0.20mol dm-3
- D. 0.40mol dm-3
Which of the following compounds with the corresponding masses contain the highest percentage of nitrogen? [N = 14]
- A. NH3 = 17
- B. NH4CI = 53.5
- C. NH4NO3 = 80
- D. (NH3)2SO4 = 132
Which of the following compounds with the corresponding masses contain the highest percentage of nitrogen? [N = 14]
- A. NH3 = 17
- B. NH4CI = 53.5
- C. NH4NO3 = 80
- D. (NH3)2SO4 = 132
What is the mass of 6.02 x 1024 atoms of magnesium? [Mg = 24, Avogadro constant = 6.02 x 1023 atoms mol-1]
- A. 240g
- B. 24 g
- C. 2.4g
- D. 0.24g