Page 2 - 3. Home Assignment - Ch-3 Concept mapping

4. Why do we use gold and platinum metals in jewelry?

5. Write one example of each of a metal which is so soft, that it can be
cut with a knife and a non-metal which is the hardest known
substance.

B] Chemical properties of Metals & Non metals-

1. Write the chemical equation for the reaction taking place when steam
is passed over hot Aluminium?

2.
What is formed when sodium absorb moisture from air? Give equation
also.

3.
Name any one metal which reacts neither with cold
water nor with hot water but reacts with heated steam to produce
hydrogen gas.

4. An element ‘A’ form two oxides AO and AO2.The oxide AO is neutral
whereas the oxide AO2 is acidic in nature. Would you call element ‘A’
a metal or a non-metal?

5.
Which of the following listed metals can displace zinc
from its salt solution? Give reason for your answer
with a chemical equation:
Copper, Lead, Magnesium, Silver

C]Ionic Bonding:

1.
Show the electronic transfer in formation of MgCl2 .

2.
Describe ionic compounds on the basis of following
properties:
a. Strong forces of attraction between positive and
negative ions.
b. Solubility of compounds in water.
c. They conduct electricity in molten state and in
aqueous solution.

3. Why are ionic compounds usually hard?

4. Give the formulae of the stable binary compounds that would be
formed by the combination of following pairs of elements.

(a) Mg and N2 (b) Li and O2 (c) Al and Cl2 (d) K and O2

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