When sodium hydroxide is heated with ammonium tetraoxosulphate (IV), the gas given off may be collected by?
- A. bubbling it through concentrated H2SO2
- B. bubbling it through water and then passing it through calcium oxide
- C. passing it directly through calcium oxide
- D. passing it directly through calcium chloride
Which of the following gases can best be used for demonstrating the fountain experiment?
i) Nitrogen (ii) Ammonia (iii) Nitrogen (I) oxide
(iv) Hydrogen chloride.
- A. ii and iii
- B. i and iii
- C. ii and iv
- D. ii only
In which of the following pairs of element is allotropy exhibited by each element?
- A. Phosphorus and hydrogen
- B. Oxygen and chlorine
- C. Sulphur and nitrogen
- D. Oxygen and sulphur
The best treatment for a student who accidentally poured concentrated tetraoxosulphate (VI) acid on his skin in the laboratory is to wash the skin with?
- A. cold water
- B. sodium hydroxide solution
- C. iodine solution
- D. sodium trioxocarbonate (IV) solution
Magnesium ribbon was allowed to burn inside a given gas P leaving a white solid residue Q. Addition of water to Q liberated a gas which produced dense white fumes with a drop of hydrochloric acid. The gas P was?
- A. nitrogen
- B. chlorine
- C. oxygen
- D. sulphur (IV) oxide
The reaction between sulphur (IV) oxide and oxygen is represented by the equilibrium reaction 2SO2(g) + O2(g) ↔ 2SO3(g), ∆H = -196 kJ. What factor would influence increased production of SO3(g)?
- A. Addition of a suitable catalyst
- B. Increase in the temperature of the reaction
- C. Decrease in the temperature of the reaction
- D. Decrease in the concentration of SO2(g)
When chlorine gas is passed into a solution of sulphur dioxide?
- A. sulphur dioxide is reduced to sulphur
- B. the chlorine is oxidized to hydrochloric acid
- C. dilute sulphuric acid and hydrochloric acid are produced
- D. Hydrochloric acid and sulphur are produced
- E. sulphur trioxide is the only product
A mixture of ethanol, sodium dichromate, and water is allowed to drop gradually into a boiling solution containing one part concentrated H2SO
4 and the liberate gas is collected by cooling it with ice water to give a liquid. This liquid is?
- A. ethanoic acid
- B. acetaldehyde
- C. ethyl acetate
- D. methanol
- E. ethylene
Which of the following statement is false?
- A. Acids react with some metals, liberating hydrogen
- B. Acids react with carbonates, liberating carbondioxide
- C. Acids conduct electricity and are decomposed by the current, liberating hydrogen at the anode
- D. Acids have a sour taste
- E. Acids change the colour of indicators
If one of the following oxides is heated with hydrogen or carbon using a bunsen burner, it is not reduced to the metal. Which one is it?
- A. Lead oxide
- B. Magnesium oxide
- C. Copper oxide
- D. Tin oxide
- E. Iron oxide
Cellulose and starches can be classified as one of the following?
- A. sugars
- B. sucrose
- C. hydrocarbons
- D. carbohydrates
- E. isomers
The best way of collecting chlorine is?
- A. by downward displacement of air
- B. by upward displacement of air
- C. over water
- D. under water
- E. over mercury
A cold aqueous solution of sodium chloride is electrolyzed using a graphite anode and an iron cathode. In the course of the electrolysis the electrolyte is continuously stirred. The liquid left after electrolysis will therefore consist of?
- A. sodium hydroxide solution
- B. chlorine water
- C. pure water
- D. sodium hypochlorite solution
- E. hydrochloric acid solution
Hardening of an oil may achieved by?
- A. boiling the oil with water
- B. boiling the oil with a catalyst
- C. treating the oil with sodium hydroxide
- D. treating the oil with hydrogen and catalyst
- E. distilling oil under reduced pressure
Hardening of an oil may be achieved by?
- A. boiling the oil with water
- B. boiling the oil with a catalyst
- C. treating the oil with sodium hydroxide
- D. treating the oil with hydrogen and catalyst
- E. distilling oil under reduced pressure
Which of the following does NOT happen when a zinc rod is introduced into a solution of copper (ll) sulphate?
- A. Electrons flow towards the zinc rod
- B. The zinc rod dissolves
- C. The temperature of the soil changes
- D. The blue colour of the solution gradually disappears
- E. Copper metal is deposited
The chemical reaction which takes place at the anode (positive electrode) in electrolysis is?
- A. oxidation
- B. hydrolysis
- C. dissociation
- D. reduction
- E. disproportionation
Which of the following silver halides is readily soluble in ammonium hydroxide?
- A. Agl
- B. AgBr
- C. AgCl
- D. AgF
- E. None of the above
In which of the following is the oxidation state of oxygen different from its value in water?
- A. OH-
- B. H3O+
- C. O-
- D. H2O2
- E. SO2
When dilute hydrochloric acid is added to iron(ll)sulphide, the gas evolved will?
- A. turn moist red litmus paper blue
- B. turn lime water milky
- C. blacken lead acetate paper
- D. rekindle a glowing splint
- E. burn a sqeakly pop
Given the mean atomic mass of chlorine prepared in the laboratory to be 35.5 and assuming that chlorine contains two isotopes of mass number 35 nad 37, what is the percentage composition of the isotope of mass number 35?
- A. 20
- B. 25
- C. 50
- D. 75
- E. 90