CBSE - Metals and Non-metals

1 Metals and Non-metals 

Silver jewellery turns blacks when exposed to air for long duration. This is due to the formation of : 

(1) Ag₂O 
(2) Ag₂S 
(3) Ag₂O + Ag₃N 
(4) AgN₃

2 Metals and Non-metals 

Consider the following pairs of elements : 

I and H , C and F,  Ba and F,  N and F,  K and O 

The correct statement regarding these pairs is : 

(1) The two pairs Ba and F, K and O most likely to form Ionic bonds 
(2) The least polar bond is formed between C and F 
(3) Bet ween I and H an ionic bond is formed 
(4) Between N and F the covalent bond is most polar

3 Metals and Non-metals 

Which of the following compounds is bad conductor of electricity?

(1) Ionic compound
(2) Electrovalent compound  
(3) Covalent compound
(4) None of these

4 Metals and Non-metals 

Which of the following gas is known as tear gas ?

(1) methyl isocyanide
(2) sulphur dioxide
(3) chloropicrin
(4) nitrous oxide

5 Metals and Non-metals 

The molecular formula of potash alum is 

(1) K₂SO₄.Al₂(SO₄)₃.24H₂O
(2) Ca(OCl)Cl
(3) )K₂SO₄
(4) Al₂(SO₄)₃.24H₂O

6 Metals and Non-metals 

A metal is strongly heated in presence of air to form a black mass. So the metal is

(1) Potassium
(2) Platinum
(3) Copper
(4) Zinc

7 Metals and Non-metals 

An element which shows allotrophy when burnt in air gives a gas with characteristic smell. The gas turns blue litmus red and is used as an insecticide. The element is

(1) C
(2) N
(3) P
(4) S

8 Metals and Non-metals 

Which of the following always contains mercury as one of the constituent ?

(1) Stainless steel
(2) Solder
(3) Duralumin
(4) Zinc Amalgam

9 Metals and Non-metals 

Calamine ore can be converted into ZnO by the process of.

(1) Dehydration
(2) Roasting
(3) Calcinations
(4) Sulphonation

10 Metals and Non-metals 

The metal which does not react with cold as well as hot water but reacts with steam is

(1) Cu 
(2) Zn 
(3) Na 
(4) Fe