Question

a=1s2,b=2s2
b=1s2,2s2,2p6,3s2
c=1s2,2s2,2p6,3s2,3p3
d=1s2,2s2,2p
1.which of this are in same group
2.which of this are same period
3.write there names and atomic number
4.which of them are nobel gas
5.find group number
6.find period number

Answer 1

Answer:

1. a and b

2. b and c

3. a - Beryllium 4

b - Magnesium 12

c - Phosphorus 15

d - Boron 5

4. none

5. a - 2

b - 2

c - 15

d - 13

6. a - 2

b - 3

c - 3

d - 2