Class 10 Science Metals & Non-metals (Solved Assignment-01)

Question 1:
Name one metal and one non-metal which exist in liquid state at room temperature.
Solution :
Metal – Mercury.
Non metal – Bromine.

Question 2:
Why are metals called electropositive elements whereas non-metals are called electronegative elements ?
Solution :
Metals are electropositive elements because they can form positive ions by losing electrons.
Non-metals are electronegative elements because they can form negative ions by gaining electrons.

Question 3:
(a) Name the most abundant metal in the earth’s crust.
(b) Name the most abundant non-metal in the earth’s crust.
Solution :
(a) Aluminium.
(b) Oxygen.

Question 4:
Name one metal which has a low melting point.
Solution :
Cesium.

Question 5:
Name the metal which is the poorest conductor of heat.
Solution :
Lead.

Question 6:
State whether the following statement is true or false :
Non-metals react with dilute acids to produce a gas which burns with a ‘pop’ sound.
Solution :
False.

Question 7:
From amongst the metals sodium, calcium, aluminium, copper and magnesium, name the metal :
(i) which reacts with water only on boiling, and
(ii) another which does not react even with steam.
Solution :
(i) Aluminium.
(ii) Copper.

Question 8:
What changes in the colour of iron nails and copper sulphate solution do you observe after keeping the iron nails dipped in copper sulphate solution for about 30 minutes ?
Solution :
Iron nail gets covered with a red-brown coating of copper metal; The blue colour of copper sulphate solution fades gradually.

Question 9:
What is aqua-regia ? Name two special metals which are insoluble in common reagents but dissolve in aqua-regia.
Solution :
Aqua-regia is a freshly prepared mixture of one part of concentrated nitric acid and 3 parts of concentrated hydrochloric acid. Gold and platinum dissolve in aqua-regia

Question 10:
Give the names and formulae of (a) two acidic oxides, and (b) two basic oxides.
Solution :
(a) Carbon dioxide and sulphur dioxide.
(b) Sodium oxide and magnesium oxide.

Question 11:
What name is given to those metal oxides which show basic as well as acidic behaviour ?
Solution :
Amphoteric oxides.

Question 12:
Name two metals which form amphoteric oxides.
Solution :
Aluminium and zinc.

Question 13:
A copper coin is kept immersed in a solution of silver nitrate for some time. What will happen to the coin and the colour of the solution ?
Solution :
Copper coin will get a shining greyish white coating of silver metal. The color of the solution will turn blue.

Question 14:
Which property of copper and aluminium makes them suitable :
(a) for making cooking utensils and boilers ?
(b) for making electric wires ?
Solution :
(a) High thermal conductivity.
(b) High electrical conductivity.

Question 15:
Write the names and formulae of (a) a metal hydride, and (b) a non-metal hydride.
Solution :
Sodium hydride,Hydrogen sulphide

Question 16:
Name the metal which has been placed :
(a) at the bottom of the reactivity series
(b) at the top of the reactivity series
(c) just below copper in the reactivity series
Solution :
(a) Gold.
(b) Potassium.
(c) Mercury.

Question 17:
Which of the two metals is more reactive : copper or silver ?
Solution :
Copper.

Question 18:
(a) Name one metal which is stored in kerosene oil.
(b) Name one non-metal which is stored under water.
Solution :
(a) Sodium.
(b) White phosphorus.

Question 19:
Write equation for the reaction of :
(a) sodium with oxygen
(b) magnesium with oxygen
Solution :

Question 20:
Name two metals which are used :
(a) for making electric wires.
(b) for making domestic utensils and factory equipment.
(c) for making jewellery and to decorate sweets.
Solution :
(a) Aluminium and copper.
(b) Copper and aluminium.
(c) Gold and silver.

Also Check:

• Class 10 Science Metals & Non-metals (Solved Assignment-02)
• Class 10 Science Metals & Non-metals (Solved Assignment-03)