CLASS 8 METALS AND NON METALS

Multiple Choice Question-
1.		The metal which is the best conductor of electricity is:
i)		gold	ii) silver		iii) copper		iv) zinc
2.		Number of naturally occurring elements:
i) 92			ii) 90		iii) 83		iv) 80
3.		Which of the following is a noble gas?
i) helium			ii) oxygen		iii) nitrogen		iv) all of these
4. All metals are solids, with the exception of:
i) aluminum			ii) graphite		iii) mercury		iv) silver
5.		A metal that is non-malleable is:
i) aluminum			ii) zinc		iii) arsenic		iv) both (ii) and (iii)
6.		A highly ductile metal is:
i) silver			ii) arsenic		iii) antimony		iv) none of these
7.		The hardest naturally occurring substance, that is a non-metal, is:
i) graphite			ii) diamond		iii) carbon		iv) none of these
	8.	The least reactive metal is:
	i)	gold		ii) silver		iii) iron		iv) sodium
	9.	Oxides of non-metals are:
	i) acidic			ii) neutral		iii) alkaline		iv) both (i) and (ii)
	10. Firemen crawl when entering a burning building because:
	i) smoke is hot and rises					ii) it is faster to move out by crawling
	iii) both(i) and(ii)					iv) none of these

Fill in the blanks:-

1.………………………. Is an exception of non-metals with high tensile strength.

2.Iron when red hot reacts with steam to form an …………………. And ………..

3.Metals react with dilute acids to form metal …………… and ………………….

4.……………………… is the only non-metal to occur as ‘liquid’.

5.……………. And …………… are exceptions of non-metals with some degree of luster.

6.……………. Is a metal that is highly ductile.

7.………………….. and ………………… are non-ductile metals.

8.Metals react with oxygen in air to form their corresponding oxides called ___________.

Very short questions:

1 marks

1.What is metallurgy?

2.What are ores?

3.Define elements?

4.What is an alloy

5.Define oxide

6.write the name of metal which is found in liquid state at room temp. 7.what is rust chemically known.

8.what is the nature of non metallic oxide. 9.what is the nature metallic oxide.

10.name two metals which can cut with knife.

Short answer questions:	(2)marks
1.How do metals differ from non-metals in terms of:
i) physical state	ii) conductivity
iii) Lustre	iv) Malleability and ductility

2.Why are sodium and potassium stored under oil? 3. List three uses of non-metals.

4.List three uses of metals?

5.What are metalloids? Give two examples.

Answer these questions:	3 marks
1.What is aqua regia?explain with example.
2.What are displacement reactions? Give one example
3.What happens when iron reacts with air?
4.What happens when metals react with dilute acids?
5.What happens when sodium reacts with water?
Long answer questions.	(5)marks

1.Differentiate between oxides of metals and oxides of non-metals giving example.

2.What is meant by ‘Reactivity Series of Metals’? Explain.

3.What is ‘displacement reaction? Give an example.

4.Why should foodstuffs like chutney, pickles and curd not be stored on containers made of metals?

5.Write the constituents and uses of the following alloys.

(Steel ,Bronze, Brass, Stainless steel)