Which of the following is not decomposed by heat?

A. CaCO₃

B. CuCO₃

C. ZnCO,sub>3

D. Na₂CO₃

E. MgCO₃

Which of the following is not true of the rusting of iron?

A. Rusting is a reduction process

B. Rusting of iron takes place in the presence of oxygen and moisture

C. the rust formed is reddish brown

D. the major constituent of rust is hydrated iron (lll) oxide

E. rusting is similar to burning

Which of the following is not true of the rusting of iron?

A. Rusting is a reduction process

B. Rusting of iron takes place in the presence of oxygen and moisture

C. the rust formed is reddish brown

D. the major constituent of rust is hydrated iron (lll) oxide

E. rusting is similar to burning

What volume of oxygen will be left unreacted when a mixture of 100cm³ of hydrogen and 200cm,sup>3,/sup> of oxygen are exploded in a eudiometer?

A. 300cm³

B. 200cm³

C. 150cm³

D. 100cm³

E. 50cm³

How many isomers can be obtained from C_4H10?

A. o

B. 1

C. 2

D. 3

E. 4

Water gas is a mixture of

A. CO_{2 and H2}

B. CO and H₂O

C. CO₂ and CO

D. CO and N₂

E. CO and H₂

Which of the following metals cannot extracted from its ore by using carbon (ll) oxide as the reducing agent?

A. Cu

B. Zn

C. Al

D. Pb

E. Fe

Which of the following is not a naturally occurring iron ore?

A. FeCl₂

B. Fe₂O₃O₃

C. Fe₂O₃

D. FeCO₃

E. FeS₂

Which of the following equations represents the reaction of chlorine with hot concentrated sodium hydroxide solution?

A. 2KOH+CI₂ → KCIO + KCI + H₂O

B. 4KOH + 2CI → 4KCI + 2H₂O + O₂

C. 6KOH + 3CI₂ → KCIO₃ + 5KCI + 3H₂O

D. 2KOH + CI₂ → 2KCI + H₂O₂

E. KOH + 2CI₂ + H₂O → KCI + 3HCI + O₂

Aqueous sodium trioxocarbonate (IV) solution is alkaline because

A. acid from which it is formed is strong

B. sodium is an alkali metal

C. sodium trioxocarbonate (IV) is decomposed by water

D. sodium trioxocarbonate (lV) is stable to heat

E. sodium triocarbonate (IV) is hydrolysed in water