The number of neutrons in ₈O¹⁶ is ________

(a)

8

(b)

16

(c)

32

(d)

24

Modern periodic law is based on __________

(a)

atomic mass

(b)

atomic number

(c)

number of neutrons

(d)

Both (a) and (b)

The first period of the modern periodic table has ________ elements.

(a)

1

(b)

2

(c)

3

(d)

8

The number of elements present in sixth period of modern periodic table is __________

(a)

8

(b)

18

(c)

16

(d)

32

Potassium belongs to ________ period

(a)

First

(b)

Second

(c)

Third

(d)

Fourth