Chromatography is used to separate components of mixtures which differ in their rates of?
- A. diffusion
- B. migration
- C. reaction
- D. sedimentaion
Which of the following reagents will confirm the presence of unsaturation in a compound?
- A. Fehling's solution
- B. Bromine water
- C. Tollen's reagent
- D. Benedict's solution
One mole of a hydrocarbon contains 48 g of carbon. If it vapour density is 28, the hydrocarbon is?
- A. an alkane
- B. an alkene
- C. an alkyne
- D. aromatic (C = 12, H = 1)
The general formula of alkanoates is?
- A. RCHO
- B. R2CO
- C. RCOOH
- D. RCOOR
When sodium is added to ethanol, the products are?
- A. sodium hydroxide and water
- B. sodium hydroxide and hydrogen
- C. sodium ethoxide and water
- D. sodium ethoxide and hydrogen
Which of the following compounds is NOT an isomers of 2,2 dimethylbutane?
- A. 2-methylbutane
- B. 3-methylpentane
- C. 2,3-dimethylbutane
- D. 2-methylpentane
Which of the following is the correct order of decreasing activity of the metals Fe, Ca, Al and Na?
- A. Fe> Ca> Al> Na
- B. Na> Ca> Al> Fe
- C. Al> Fe> Na> Ca
- D. Ca> Na> Fe>, Al
Which of the following is NOT true of metals?
- A. They are good conductors of electricity
- B. They ionize by electron loss
- C. Their oxides are acidic
- D. They have high melting points
In an electrolytic set-up to protect iron from corrosion, the iron is?
- A. made cathode
- B. made anode
- C. used with a metal of lower electropositive potential
- D. initially coated with tin
SO3 is NOT directly dissolved in water in the preparation of H2SO4 by the contact process because?
- A. the reaction between SO3 and water is violently exothermic
- B. acid is usually added to water and never water to acid
- C. SO3 does not dissolve in water readily
- D. SO3 is an acid gas
Which of these solutions will give a white precipitate with a solution of barium chloride acidified with hydrochloric acid?
- A. Sodium trioxocarbonate (IV)
- B. Sodium tetraoxosulphate (IV)
- C. Sodium trioxosulphate (IV)
- D. Sodium sulphide
Clothes should be properly rinsed with water after bleaching because?
- A. the bleach decolourizes the cothes
- B. chlorine reacts with fabrics during bleaching
- C. the clothes are sterilized during bleaching
- D. hydrogen chloride solution is produced during bleaching
Which of these metals CANNOT replace hydrogen from alkaline solutions?
- A. Alulinium
- B. Zinc
- C. Tin
- D. Iron
Which of the following are produced when ammonium trioxonitrate (V) crystals are cautiously heated in a hard glass round bottomed flask?
- A. N2O and steam
- B. NO2 and ammonia
- C. N2O2 and NO2
- D. NO and NO2
Which of the following is TRUE of Le Chatelier’s Principle for an exothermic reaction?
- A. Increase in temperature will cause an increase in the equilibrium constant
- B. Increase in temperature will cause a decrease in the equilibrium constant
- C. Addition of a catalyst will cause an increase in the equilibrium constant
- D. Addition of a catalyst will cause a decrease in the equilibrium constant
MnO4(aq) + 8H + (aq) + 5Fe2+ → Mn2+(aq) + 4H2O(I). The oxidation number of manganese in the above reaction changed from?
- A. +7 to +2
- B. +6 to +2
- C. +5 to +2
- D. +4 to +2
An anhydride is an oxide of non-mental
- A. which will not dissolve in water
- B. whose solution in water has a pH greater than 7
- C. whose solution in water has a pH less than 7
- D. whose solution in water has a pH of 7
H– + H2(I)O → H2(g) + OH–(aq). From the equation above, it can be inferred that the?
- A. reaction is a double decomposition
- B. hydride ion is a reducing agent
- C. hydride ion is an oxidizing agent
- D. reaction is neutralization
Crude copper could be purified by the electrolysis of concentrated copper (II) chloride if the crude copper is?
- A. made both the anode and the cathode
- B. made the cathode
- C. made the anode
- D. dissolved in the solution
What volume of Oxygen measured at s.t.p would be liberated on electrolysis by 9650 coulombs of electricity?
(Molar volume of gas = 22.4 dm\(^3\), 1F = 96,500 C/mol)
- A. 22.4 dm3
- B. 11.2 dm3
- C. 1.12 dm3
- D. 0.560 dm3
20 cm3 of a 2.0 M solution of ethanoic acid was added to excess of 0.05 M sodium hydroxide. The mass of the salt produced is?
(Na = 23, C = 12, O = 16, H = 1)
- A. 2.50 g
- B. 2.73 g
- C. 3.28 g
- D. 4.54 g