A major factor considered in selecting a suitable method for preparing a simple salt is its
- A. crystalline form
- B. melting point
- C. reactivity with dilute acids
- D. solubility in water
The gas given off when NH4Cl is heated with an alkali is
- A. H2
- B. CI2
- C. N 2
- D. NH 3
What volume of hydrogen will be produced if 100cm3 of ammonia is completely decomposed at constant temperature and pressure? The equation for the reaction is 2NH3(g) → N2(g) + 3H2(g)
- A. 50cm3
- B. 150cm3
- C. 200cm3
- D. 300cm3
Which of the following decreases when a given mass of gas is compressed to half its initial volume?
- A. Average intermolecular distance
- B. Frequency of collisions
- C. Number of molecules present
- D. Atomic radius of each particle
If a metal R forms a compound with the formula R(NO3)2 the formula of its tetraoxosulphate (VI) is
- A. R(SO4)2
- B. RSO4
- C. R2SO4
- D. R2(SO4)3
The conclusion from Rutherford’s radioactive substance alpha-scattering experiment is that
- A. atoms are mostly empty space with a samll
- B. emissions from radioactive substances consist of three main components
- C. there is unclear pull on orbital electrons
- D. electrons are deflected by both magnetic and electric fields
The atomic number of chlorine is 17. What is the number of electrons in a chloride ion?
- A. 16
- B. 17
- C. 18
- D. 19
If the relative molecular mass of an element is not a whole number, it can be deduced that the element is
- A. naturally radioactive
- B. abundant in nature
- C. a transition metal
- D. an isotopic mixture
Waste plastics accumulate in the soil and pollute the environment because plastic materials are
- A. insoluble in water
- B. non-biodegradable
- C. easily affected by heat
- D. inflammable
Acidic industrial waste can be treated with
- A. lime
- B. brine
- C. water
- D. ethanol
Which of the following reactions represents the change that occurs when a photographic film is exposed to sunlight?
- A. Ag → Ag+ + e-
- B. Ag+ + e- → Ag
- C. 2Ag + Br22 → AgBr
- D. Ag+ + Br- → AgBr
If 10 cm 3 of distilled water is added to 10 cm3 of an aqueous salt solution, the concentration of the solution
- A. increases
- B. decreases
- C. remains constant
- D. doubles
Sugars can be hydrolyzed at room temperature by the action of
- A. mineral acids
- B. strong bases
- C. enzymes
- D. oxidants
Which of the following constitutes an advantage in the use of hard water?
- A. Formation of scum with soap
- B. Furring of kettles
- C. Blockage of water pipes
- D. Formation of strong bones
What is the function of H2SO4 in the following reaction?
C12H22O11 conc. H2SO4 → 12C + 11H2O
- A. Oxidizing agent
- B. Strong acid
- C. Dehydrating agent
- D. Catalyst
Which of the following polymers contains nitrogen?
- A. Nylon
- B. Polyvinyl chloride
- C. Polyethene
- D. Cellulose
One of the products of combustion of pentane in excess air is
- A. pentanol
- B. pentene
- C. nitrogen (ll) oxide
- D. carbon (IV) oxide
Benzene produces more soot than ethene on burning because benzene
- A. has a higher molar mass
- B. has a higher degree of unsaturation
- C. undergoes substitution and addition reactions
- D. is a liquid at room temperature
Hydrogenation of butene yields
- A. butyne
- B. butane
- C. pentence
- D. butanol
A feasible cell was constructed by joining the two half cells below. Cu2+ (aq) + 2e- → Cu(s) Eo = +0.34 V; Zn\({^2+}\) + 2e\(^-\) → Zn\((_s)\) Eo = – 0.76V. What is the standard e.m.f. of the cell?
- A. - 1.1V
- B. - 0.42V
- C. +0.42V
- D. +1.1V
In the electrolysis of CuSO4(aq) using copper electrodes, the reaction at the anode is
- A. discharge of SO4 2-
- B. discharge of OH-
- C. dissolution of copper electrode
- D. evolution of oxygen