Sugar is separated from its impurities by
- A. precipitation
- B. crystallization
- C. distillation
- D. evaporation
Which of these properties gives a solid its definite shape?
- A. strong intermolecular attraction
- B. high melting point
- C. high boiling point
- D. weak intermolecular attraction
The shape of the hydrocarbon compound CH4 is
- A. square planar
- B. planar
- C. linear
- D. tetrahedral
How many moles of limestone will be required to produce 5.6g of CaO?
[Ca = 40, C = 12, O= 16]
- A. 0.20 mol
- B. 0.10 mol
- C. 1.12 mol
- D. 0.56 mol
Natural water collected from rivers and ponds contain oxygen, carbon (IV) oxide and
- A. nitrogen
- B. hydrogen
- C. chlorine
- D. sulphur
- E. oxide
The gas that is the most dangerous pollutant to human is
- A. sulphur (IV) oxide
- B. carbon (IV) oxide
- C. nitrogen (II) oxide
- D. hydrogen sulphide
Kerosine is commonly used to remove the red colour stain of palm oil from cloths because it
- A. helps to spread the oil over a larger surface area
- B. react with the oil to form an odourless compound
- C. makes the oil evaporate easily by dissolving it
- D. helps to dilute the oil and reduce its colour
The air around smelting industries is likely to contain
- A. H2S, CO and N2
- B. CO2, SO3 and H2
- C. H2, SO2 and CO2
- D. SO2, N2 and CO2
The solubility curve shows the variation of solute concentration with
- A. volume
- B. temperature
- C. vapour density
- D. pressure
25cm3 of a mixture of nobel gases was obtained from air after the removal of other constituents. What was the original volume of air
- A. 2,500 cm3
- B. 1250 cm3
- C. 125 cm3
- D. 80 cm3
When water boilers are used for long period of time, the solid substances left behind as scale are
- A. magnesium trioxosilicate (IV) and rust
- B. magnesium trioxosilicate (IV) and calcium tetraoxosulphate (VI)
- C. clay and magnesium troxosulphate (IV)
- D. clay and rust
A substance that is used as a ripening agent for fruits is?
- A. ethene
- B. propene
- C. methane
- D. butane
Equal moles of ethyne and hydrogen iodide react to give
- A. CH2 = CH2
- B. CH2 - CHI
- C. CH3 - CI
- D. CH2 = CHI
How many hydrogen atoms does a single ring cycloalkane have less than the corresponding open-chain alkane?
- A. Two
- B. Three
- C. Four
- D. One
In the purification of impure samples of ethyl ethanoate synthesized by esterification, concentrated sodium trioxocarbonate (IV) solution is used to remove
- A. water
- B. basic impurities
- C. acidic impurities
- D. ethoxyethane
Which of the following are structural isomers?
- A. propanoic acid and propan-1, 2-diol
- B. Propanal and propanone
- C. Ethanoic acid and propanoic acid
- D. Ethan-1, 2-diol and ethanoic acid
The decolourization of purple colour of tetraoxomanganate (VII) ion is a test for
- A. alkenes
- B. alkanols
- C. alkanals
- D. alkanes
The enzymes responsible for converting sucrose into two simple isomeric sugars is
- A. maltase
- B. amylase
- C. invertase
- D. lactase
What will happen if an aluminium spoon is used to stir a solution of iron (II) trioxonitrates (V)?
- A. The spoon will be oxidized while the iron (II) ions will be reduced to the metal
- B. The spoon will increase in size
- C. The spoon will be reduced while the iron (II) ions will be oxidized
- D. The spoon will be reduced
What is the correct IUPAC name for NO\(_{2} ^{-}\)?
- A. Dioxonitrate (IV) ion
- B. Trioxonitrate (III) ion
- C. Trioxonitrate (IV) ion
- D. Dioxonitrate (III) ion
When sulphur (IV) oxide is passed into a solution of sodium hydroxide for a long time, it eventually produces a solution of
- A. NaHSO4
- B. Na2SO3
- C. NaHSO3
- D. Na2SO4