PERIODIC CLASSIFICATION OF ELEMENTS

An atom of an element has the electronic confi-guration 2,8,2. To which group does it belong?

• (a) 4th group

• (b) 6th group

• (c) 3rd group

• (d) 2nd group

The arrangement of elements in the Modem Periodic Table is based on their

• (a) increasing atomic mass in the period

• (b) increasing atomic number in the horizontal rows

• (c) increasing atomic number in the vertical columns

• (d) increasing atomic mass in the group

Where would you locate the element with electronic configuration 2, 8 in the Modern Periodic Table?

• (a) Group 8

• (b) Group 2

• (c) Group 18

• (d) Group 10

Element ‘X’ forms a chloride with the formula XCl2, which is a solid with high melting point. X would most likely be in the same group of the periodic table as:

• (a) Si

• (b) Mg

• (c) Al

• (d) Na

Carbon belongs to the second period and Group 14. Silicon belongs to the third period and Group 14. If atomic number of carbon is 6, the atomic number of silicon is

• (a) 7

• (b) 14

• (c) 24

• (d) 16

The elements A, B and C belong to groups 1, 14 and 17 respectively of the Periodic Table. Which two elements will form ionic compounds?

• (a) A and B

• (b) A and C

• (c) B and C

• (d) None

An element ‘A’ belongs to the third period and group 16 of the Periodic Table. Find out the valency of A.

• (a) Valency = 6

• (b) Valency = 2

• (c) Valency = 1

• (d) Valency = 3

The atom of an element has electronic con-figuration 2, 8, 7. To which of the following elements would it be chemically similar?

• (a) N(7)

• (b) P(15)

• (c) Na(11)

• (d) F (9)

Atoms of elements in group 1 have ____________.

• one electron in their outermost energy level

• two electrons in their outermost energy level

• seven electrons in their outermost energy level

• eight electrons in their outermost energy level

Up to which element,law of octaves found to be applicable

• Oxygen

• Calcium

• Cobalt

• Potassium