Class – 10 th (Chemistry Worksheet )
Ch. – 1 & 2
Q1. Answer the following questions:
1. Which period is the shortest one?
2. In which period maximum number of elements is present?
3. An element with atomic number 20 belongs to which period and group.
4. All the non-metals are placed at which place in the modern periodic table.
5. Give the name and the symbol of the elements which occupy the following positions in
the periodic table :
Period 4, group II A
Period 2, group IIIA
Period 3, group zero
Period 2, group VI A
Period 3, group IV A
6. A group of elements in the Periodic Table are given below (Boron is the first member of
the group and Thallium is the last).
Boron, Aluminum, Gallium, Indium, Thallium
Answer the following questions in relation to the above group of elements:
a. Which element has the most metallic character?
b. Which element would be expected to have the highest electro-negativity?
c. If the electronic configuration of Aluminum is 2, 8, 3, how many electrons are there in
the outer shell of Thallium?
d. The atomic number of Boron is 5.Write the chemical formula of the compound
formed when Boron reacts with Chlorine.
e. Will the elements in the group to the right of this Boron group be more metallic or
less metallic in character? Justify your answer.
7. Two different elements A and B have atomic number 12 and 14 respectively, Write down:
a. The electronic configuration of X and Y.
b. The groups of Periodic Table to which they belong.
c. The valency of each element.
d. The formulae of their simplest chlorides.
e. The explanation for the following:
f. The chloride of one is a good conductor of electricity in molten state, while the
other is not.
g. Write the formula of the sulphate of the element with atomic number 13.
8. Chlorine, bromine and iodine elements were put in one group on the basis of the similar
properties:
a. What are those similar properties?
b. What is the common name of this group or family?
9. Give two examples of polar covalent compounds and two examples of non-polar covalent
compounds.
10. Match the following columns A and B.
Column A Column B
A. Metal a)Methane (CH4)
B. Covalent compound b)Sodium chloride (NaCl)
C. Non-polar c) Selenium (Se)
D. Polar d) Chloride ion (Cl-)
E. Non-metal e)Aluminum (Al)
F. Electrovalent compound f)Carbon dioxide (CO2)
G. Anion g) Hydrogen Chloride (HCl)
H. Cation h) Potassium ion (K+)
11. On what factors the formation of an ionic compound depends?
12. Which conditions are necessary for the formation of co-ordinate bond?
13. Explain the formation of H3O+ and NH4+ ion.
14. Give one property of hydrogen chloride which agrees with it being a covalent compound.
15. Give one property of magnesium chloride which agrees with it being an ionic compound.
16. Which property of the compound agrees with the being of a covalent compound?
17. What are the conditions for the formation of an electrovalent bond ?
18. Predict the type of bond (ionic or covalent) likely to be formed when pair elements having
atomic number combine:
a. 3 and 7
b. 6 and 9
c. 11 and 16
d. 14 and 12
e. 8 and 16
19. The distribution of electrons in three elements is as under: U = 2, 6; V = 2, 8, 7 and W =
2, 8, 1.Use the letter U, V and W as the symbols of elements in answering the following
questions. In each case, state whether the bonding is ionic or covalent, and give the
formula of molecule or compound formed:
a. Between two atoms of U
b. Between U and W
c. Between V and W.
