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
Which of these alloys contains copper?
- A. solder
- B. steel
- C. permallory
- D. bronze
Calculate the percentage composition of oxygen in calcium trioxocarbonate(IV) [Ca=40, C=12, O=16]
- A. 16
- B. 48
- C. 40
- D. 12
The ionic radii of metals are usually
- A. greater than their atomic radii
- B. unaffected by the charge on the ion
- C. the same as their atomic radii
- D. less than their atomic radii
In electrovalency, the oxidation number of the participating metal is always
- A. decreasing
- B. increasing
- C. constant
- D. neutral
The derivative of benzene that can be used in making explosives is
- A. aniline
- B. xylene
- C. phenol
- D. toluene
During the electrolysis of copper II sulphate between platinum electrodes, if litmus solution is added to the anode compartment
- A. the litmus turns blue but no gas is evolved
- B. the litmus turns blue and oxygen is evolved
- C. the litmus turns blue and hydrogen is evolved
- D. the litmus turns red and oxygen is evolved
Elements P, Q, R, S have 6, 11, 15, 17 electrons respectively, therefore,
- A. P will form an electrovalent bond with R
- B. Q will form a covalent bond with S
- C. R will form an electrovalent bond with S
- D. Q will form an electrovalent bond with S