A form of carbon used for absorbing poisonous gases and purification of noble gases is

• A. wood charcoal
• B. animal charcoal
• C. carbon fibres
• D. carbon black

Synthesis gas is a mixture of

• A. CH4 and H2O
• B. CH4 and H2
• C. CO2 and H2
• D. CO and H2

The repeating unit in natural rubber is

• A. alkyne
• B. isoprene
• C. n-propene
• D. peoprene

The ratio of the initial to final pressure of a given mass of gas is 1:1.5. Calculate the final volume of the gas if the initial volume was 300 cm³ at the same temperature

• A. 120 cm³
• B. 200 cm³
• C. 450 cm³
• D. 750 cm³

Potassium vapour burns with a

• A. blue flame
• B. brick-red flame
• C. violet flame
• D. golden-yellow flame

Sieving is a technique used to separate mixture containing solid particles of

• A. small sizes
• B. large sizes
• C. differents sizes
• D. the same sizes

Haematite is an ore of

• A. zinc
• B. lead
• C. iron
• D. copper

For a reaction in equilibrium, the species involved in the equilibrium constant expression are

• A. gaseous and solid species
• B. liquid and solid species
• C. solid and dissolved species
• D. gaseous and dissolved species

The distance between the nuclei of chlorine atoms in a chlorine molecule is 0.194 mm. The atomic radius of chlorine atom is

• A. 0.097 mm
• B. 0.194 mm
• C. 0.388 mm
• D. 2.388 mm

A common characteristics of copper and silver in their usage as coinage metals is that they

• A. have high metallic lustre
• B. are not easily oxidized
• C. are easily oxidized
• D. are not easil reduced