A reaction is endothermic if the
- A. reaction vessel feels cool during the reaction
- B. enthalpy change is negative
- C. bond forming energy exceeds bond breaking energy
- D. heat of formation of reactants exceeds heat of formation of products
An acidic salt has
- A. double anions in its aqueous solution
- B. a single cation in its aqueous solution
- C. hydrogen ions in its aqueous solution
- D. hydrogen atoms in its aqueous solution
What is the solubility of a salt if 0.4g of it is obtained on evaporating 200\(cm^{3}\) of its saturated solution to dryness?
- A. 0.08\(gdm^{-3}\)
- B. 2.00\(gdm^{-3}\)
- C. 8.00\(gdm^{-3}\)
- D. 80.00\(gdm^{-3}\)
The process of extraction of iron from its ore is
- A. decomposition
- B. oxidation
- C. reduction
- D. sublimation
Which of the following equations represents a redox reaction?
- A. \(HNO_{{3}{(aq)}} + NaOH_{(aq)} \to NaNO_{{3}{(aq)}} + H_{2}O_{(l)}\)
- B. \(AgNO_{{3}{(aq)}}+KCl_{(aq)} \to AgCl_{(s)}+KNO_{{3}{(aq)}}\)
- C. \(CaCO_{{3}{(s)}} \to CaO_{(s)} + CO_{{2}{(g)}}\)
- D. \(2H_{2}S_{(s)} + SO_{{2}{(g)}} \to 2HO_{2} + 3S_{(g)}\)
Which of the following organic compounds can undergo both addition and substitution reactions?
- A. Pentane
- B. Benzene
- C. Propane
- D. Hexane
Which of the following raw materials is used in the plastic industry?
- A. Ethene
- B. Methane
- C. Sulphur
- D. Hydrogen
In the upper atmosphere, the ultra-violet light breaks off a free chlorine atom from chlorofluorocarbon molecule. The effect of this is that the free chlorine atom will
- A. be very reactive and will attack ozone
- B. be non-reactive and will not attack ozone
- C. not change the level of ozone in the atmosphere
- D. increase the level of ozone in the atmosphere
Which of the following separation techniques can be employed in obtaining solvent from its solution?
- A. Evaporation
- B. Distillation
- C. Filtration
- D. Precipitation
A sample of hard water contains some calcium sulphate and calcium hydrogen carbonate. The total hardness may therefore be removed by
- A. boiling the water
- B. adding excess calcium hydroxide
- C. adding a calculated amount of calcium hydroxide
- D. adding sodium carbonate
In the removal of water hardness, permutit is regenerated with a strong solution of
- A. NaOH
- B. Na\(_3\)SO\(_4\)
- C. Na\(_3\)CO\(_3\)
- D. NaCl
When large hydrocarbon molecules are heated at high temperature in the presence of a catalyst to give smaller molecules, the process is known as
- A. disintegration
- B. polymerization
- C. cracking
- D. degradation
Which of the compounds is composed of Al, Si, O and H?
- A. Epson salt
- B. Limestone
- C. Clay
- D. Urea
H\(_2\) S\(_{(g)}\) + Cl\(_{2(g)}\) β 2HCl\(_{(g)}\) + S\(_{(g)}\) In the reaction above, the substance that is reduced is
- A. H\(_2\)S
- B. S
- C. HCl
- D. Cl\(_2\)
The elements in the periodic table are listed in order of increasing
- A. relative atomic number
- B. atomic mass
- C. relative isotopic mass
- D. nuclear charge
The alkanoic acid found in human sweat is
- A. CH\(_3\)-COOH
- B. CH\(_3\)βCH\(_2\)βCOOH
- C. H-COOH
- D. CH\(_3\)
The general formula of alkanones is
- A. RCHO
- B. R\(_2\)CO
- C. RCOOH
- D. RCOOR
The situation obtained when a perfect gas expands into a vacuum is
- A. ΞH is positive and TΞ S is zero
- B. ΞH is positive and T Ξ S is negative
- C. ΞH is negative and TΞ S is zero
- D. ΞH is zero and T Ξ S is positive
3H\(_{2(g)}\)+ N\(_{2(g)}\)β 2NH\(_{3(g)}\) ; H= -ve
In the reaction above, lowering of temperature will
- A. have no effect on the equilibrium position
- B. increase the rate of both the forward and reverse reactions equally
- C. favour the forward reaction
- D. favour the reverse reaction
Sieving is a technique used to separate mixtures containing solid particles of
- A. small sizes
- B. large sizes
- C. different sizes
- D. the same size
If the molecular mass of tetraoxosulphate (VI) acid is 98, calculate its vapour density.
- A. 196
- B. 49
- C. 106
- D. 82