EASY
10th CBSE
IMPORTANT
Earn 100

Give reason:

Metals like sodium and potassium are stored under oil.

Important Questions on Metals and Non-metals

EASY
10th CBSE
IMPORTANT
Silver articles become black when kept in open for some time, whereas copper vessels lose their shiny brown surfaces and gain a green coat when kept in open. Name the substances present in air with which these metals react and write the name of the products formed.
HARD
10th CBSE
IMPORTANT
Carbon cannot reduce the oxides of sodium, magnesium and aluminium to their respective metals. Why? Where are these metals placed in the reactivity series? How are these metals obtained from their ores? Take an example to explain the process of extraction along with chemical equations.
MEDIUM
10th CBSE
IMPORTANT

A student, took four metal P, Q, R and S and earned out different experiments to study the properties of metals. Some of the observations were: 

  •  All metals could not be cut with knife except metal R.
  •  Metal P combined with oxygen to form an oxide M2O3 which reacted with both acids and bases. 
  •  Reaction with water. 

P — Did not react either with cold or hot water but reacted with steam

Q — Reacted with hot water and the metal started floating  

R — Reacted violently with cold water.  

S — Did not react with water at all.

Based on the above observations answer the following:

Out of the given metals, the one which needs to be stored used kerosene is-

MEDIUM
10th CBSE
IMPORTANT

A student, took four metal P, Q, R and S and earned out different experiments to study the properties of metals. Some of the observations were: 

  •  All metals could not be cut with knife except metal R.
  •  Metal P combined with oxygen to form an oxide M2O3 which reacted with both acids and bases. 
  •  Reaction with water. 

P — Did not react either with cold or hot water but reacted with steam

Q — Reacted with hot water and the metal started floating  

R — Reacted violently with cold water.  

S — Did not react with water at all.

Based on the above observations answer the following:

Out of the given metals, the metal Q is:

EASY
10th CBSE
IMPORTANT

A student, took four metal P, Q, R and S and earned out different experiments to study the properties of metals. Some of the observations were: 

  •  All metals could not be cut with knife except metal R.
  •  Metal P combined with oxygen to form an oxide M2O3 which reacted with both acids and bases. 
  •  Reaction with water. 

P — Did not react either with cold or hot water but reacted with steam

Q — Reacted with hot water and the metal started floating  

R — Reacted violently with cold water.  

S — Did not react with water at all.

Based on the above observations answer the following:

Metal which forms amphoteric oxides is:

MEDIUM
10th CBSE
IMPORTANT

A student, took four metal P, Q, R and S and earned out different experiments to study the properties of metals. Some of the observations were: 

  •  All metals could not be cut with knife except metal R.
  •  Metal P combined with oxygen to form an oxide M2O3 which reacted with both acids and bases. 
  •  Reaction with water. 

P — Did not react either with cold or hot water but reacted with steam

Q — Reacted with hot water and the metal started floating  

R — Reacted violently with cold water.  

S — Did not react with water at all.

Based on the above observations answer the following:

The increasing order of the reactivity of four metals is:

EASY
10th CBSE
IMPORTANT
The electron dot structure of chlorine molecule is:
EASY
10th CBSE
IMPORTANT

Metal oxides generally react with acids, but few oxides of metal also react with bases. Such metallic oxides are:

I. MgOII. ZnOIII. Al2O3IV. CaO