Waec Chemistry Past Questions
Question 21
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
Question 22
Which of the following is not decomposed by heat?
- A. CaCO3
- B. CuCO3
- C. ZnCO,sub>3
- D. Na2CO3
- E. MgCO3
Question 23
Bubbling of carbon (IV)oxide into calcium hydroxide solution results in the formation of
- A. CaCO3
- B. CuCO3
- C. ZnCO,sub>3
- D. Na2CO3
- E. MgCO3
Question 24
Which of the following equations represents the reaction of chlorine with hot concentrated sodium hydroxide solution?
- A. 2KOH+CI2 → KCIO + KCI + H2
- B. 4KOH + 2CI → 4KCI + 2H2O + O2
- C. 6KOH + 3CI2 → KCIO3 + 5KCI + 3H2O
- D. 2KOH + CI2 → 2KCI + H2O2
- E. KOH + 2CI2 + H2O → KCI + 3HCI + O2
Question 25
Which of the following is not a naturally occurring iron ore?
- A. FeCl2
- B. Fe2O3O3
- C. Fe2O3
- D. FeCO3
- E. FeS2
