Materials: Metals and Non-Metals

Q1. Fill in the blanks.

                         i.        Phosphorus is very reactive non-metal.

                        ii.        Metals are good conductors of heat and electricity.

                       iii.        Iron is more reactive than copper.

                       iv.        Metals react with acids to produce hydrogen gas.

                        v.        Most non-metals are bad conductors of heat.

                       vi.        Metals are lustrous.

         vii.        Some metals react with water to produce metal hydroxides and hydrogen gas.

         viii.        Metals can be distinguished from non-metals on the basis of their physical and chemical properties.

                       ix.        A sample of an element contains only one kind of atoms.

Q2. True/False

                         i.        Generally, non-metals react with acids. False

                        ii.        Sodium is a very reactive metal. True

                       iii.        Copper displaces zinc from zinc sulphate solution. False

                       iv.        Coal can be drawn into wires. False

                       v.        Metals are harder than non-metals. True

                      vi.        Metal reacts with oxygen to form metallic oxides. True

Q3. Which is more reactive iron or copper?

Ans. Iron

Q4. Which is less reactive sodium or gold?

Ans. Gold

Q5. Which one of the two is malleable oxygen or calcium?

Ans. Calcium

Q6. Which of the two is malleable, phosphorus or iron?

Ans. Iron

Q7. Which metal is used to make foil to wrap food items?

Ans. Aluminium metal

Q8. Which metal foil is used to decorate sweets?

Ans. Silver foil used for decorating sweets.

Q9. The shape of the iron nail and the aluminium wire changes on beating. Which property of metals is shown by this?

Ans. Property of malleability

Q10. What is atom?

Ans. The smallest unit of an element is atom.

Q11. How many naturally occurring elements are there?

Ans. There are no more than 92 naturally occurring elements.

Q12. Why metals are said to be sonorous?
Or
Why are metals sonorous?

Ans. Since metals produce ringing sounds, they are said to be sonorous.

Q13. Why non-metals cannot be drawn into wires?

Ans. Non-metals are not ductile. Therefore they cannot be drawn into wires.

Q14. Which of the following can be beaten into thin sheets?
(a) Zinc (b) Phosphorus (c) Sulphur (d) Oxygen

Ans. Zinc

Q15. Which of the following statements is correct?
(a) All metals are ductile.
(b) All non-metals are ductile.
(c) Generally, metals are ductile.
(d) Some non-metals are ductile.

Ans. Generally, metals are ductile.

Q16. Complete the following displacement reaction:
Copper sulphate + ______ -----> Zinc sulphate + ______?

Ans. Copper sulphate + zinc -----> Zinc sulphate + copper

Q17. Name the non-metal essential for our life, which all living being inhale during breathing.

Ans. Oxygen

Q18. Which of the two will produce ringing sound a metallic box or a wooden box and why?

Ans. A metallic box will produce ringing sound because metals are sonorous.

Q19. There are two materials A and B. On hammering A is flattened, but B breaks. Which one is a metal?

Ans. A is a metal because it flattens, i.e., it is malleable.

Q20. Name two soft metals which can be cut with a knife.
Or
What are soft metals that can be cut with a knife?
Or
Why can sodium and potassium be cut with a knife?
Or
Which metals can be cut by a knife?

Ans. Metals like sodium and potassium are soft and can be cut with a knife.

Q21. Give some examples of non-metals.

Ans. The examples of non-metals are sulphur, carbon, oxygen, phosphorus, etc.

Q22. Give some examples of metals.

Ans. The examples of metals are iron, copper, aluminium, calcium, magnesium, etc.