Metals and Non Metals Important Question and Answers

One Word Answers

1.Which metal is liquid at room temperature other than mercury?
Ans.Gallium
2.Which non metal is lustrous and shiny?
Ans.Iodine

3.Which non metal is good conductor of Electricity?
Ans.Graphite
4.Which Metals can be cut with Knife?
Ans.Sodium,Potassium,Lithium
5.Which Metals have very low melting and boiling point?
Ans.Gallium and Ceasium
6.A reaction in which more reactive metal displaces less reactive metal from its salt solution
Ans.Displacement reaction
7.Which non metal is liquid at room temeprature
Ans.Bromine
8.Which is the hardest element known to mankind
Ans.Diamond
9.Metal Oxides which show both basic and acidic nature
Ans.Amphoteric oxides  (Aluminium oxide, Zinc Oxide)
10.Sulphur is stored in....
Ans.Water
11.Sodium, and Potassium are usually kept in...
Ans.Keroscene
12.Some elements show property of both metals and non metals
Ans.Metalloids
13.Compound formed by transform of electrons from Metals to Non Metals
Ans.Ionic Compound
14.the damage caused to metals due to the reaction of metals with oxygen, moisture, carbon dioxide etc. 
Ans.Corrosion
15.A mixture of concentrated nitric acid and concentrated hydrochloric acid in the ratio 1:3.

 16.A pencil lead is made up of Non Metal called
Ans.Graphite
17:Hard and brittle form of iron with a high carbon content is :-
Ans:Pig Iron
18. Tough and Malleable form of iron is
Ans.Wrought Iron


Question and Answers

Q1.Cooking utensils are made of metals but their handles are made of wood or plastic,Why ?
Ans. Cooking utensils are made of metals because metals are good conductors of heat so that heat gets conducted in a proper way from the fire( cooktop or induction cookerheat) into the food which is being cooked.On the other hand, the handles of cooking utensils must be held time to time during cooking. Since metallic handles will be very hot to hold thus handles are made fromany plastic or wood which are bad conductors of heat.
Q2.Why is it advised not to store pickles and curd in metallic utensils ?
Ans.Kitchen  utensils  are  generally  made  up  of  metals  like  iron  These
metals  are  quite  reactive  and  due  to  the  reaction  between  acid  present  in  pickle  or
curd and the utensil metal, a toxic substance may be formed. This can harm our health.
Q3.Other than iron do any metal get rusted?If yes explain how
Ans.Yes copper gets rusted in moist air and acuires a dull green coating.Copper gets corroded or rusted in the presence of carbon dioxide and water to form a green coating,which is mixture of copper hydroxide and copper carbonate.
Q4.How will you prove the nature of metal oxides?
Ans.If we burn a magnesium ribbon, white ash of magnesium oxide is formed. Now by
adding little water to white ash we can prepare solution of magnesium oxide. When
we dip red litmus paper into this solution it turns blue while when we dip blue litmus  paper into this solution colour remains unchanged. It proves that metal oxides are basic in nature.
Q5.Write down any five important uses of metals ?
Ans. Lead is used in X-ray machines.

(ii) Iron is used in construction.

(iii) Mercury is used in thermometers.

(iv) Gold and silver are used in making jewellery.

(v) Aluminium foil is used for packing food.
Q6.What are noble metals?
Ans.Some of the metals are more reactive while other are less reactive. But there are
certain  metals  that  are  very  unreactive  as  they  do not  react  with  oxygen,  water,
moisture, or even any of the dilute acids for example gold and platinum. Therefore
such metals are called as noble metals.
Q7. List any five important uses of non metals ?
Ans. i) Sulphur is used in vulcanization of rubber,which makes rubber sufficiently hard

to produce tyres.

(ii) Phosphorus is used in making phosphatic fertilizers.

(iii) Graphite is used in making lead of pencils.

(iv) Hydrogen can be used as a fuel that will be a non polluting option of fuel.

(v) Chlorine is added to water for purification purpose.
Q8.What would happen if sodium and potassium are kept in open air?
Ans. Both  sodium  and  potassium  are  highly  reactive  metals.  They  react  violently  (may catch fire) with oxygen and moisture present in air
 even at the room temperature. A lot of heat is evolved when such reaction occurs and as such the metal is lost because it makes oxides. Hence these extremely reactive metals are not kept in open but are kept immersed in the kerosene.

CBSE class 8 NCERT Question Answers from Metals and Non Metals