Question 706:

• JAMB 1991

Oxygen gas can be prepared by heating?

A. Ammonium trioxonitrate (V)
B. Ammonium trioxonitrate (III)
C. Ppotassium trioxonitrate (V)
D. Mamgamese (IV) oxide

Question 707:

• JAMB 1991

Addition of aqueous ammonia to a solution of Zn⁺⁺ gives a white precipitate which dissolves in an excess of ammonia because?

A. Zinc is amphoteric
B. Zinc hydroxide is readily soluble
C. Zinc forms a complex which is readily soluble in excess ammonia
D. Ammonia solution is a strong base

Question 708:

• JAMB 1991

Which of the following, in clear solution, forms a white precipitate when carbon (IV) oxide is bubbled into it for a short time?

A. KOH
B. NaOH
C. Ca(OH)₂
D. AI(OH)₃

Question 709:

• JAMB 1991

Which of the following metals can be prepared in samples by the thermal decomposition of their trioxonitrate (V) salts?

A. Copper and mercury
B. Silver and copper
C. Mercury and silver
D. Magnesium and mercury

Question 710:

• JAMB 1991

Copper (II) tetraoxosulphate (IV) is widely used as a?

A. Fertilizer
B. Fungicide
C. Disinfectant
D. Purifier