Question

Choose the appropriate pair of atoms that contain the same number of neutrons.

(Example: ^13 6C = ¹³₆C, ^13 7N = ¹³₇N and so on)

^13 6C and ^13 7N

^37 17Cl and ^36 18Ar

^18 8O and ^19 9F

^6 3Li and ^7 3Li

Answer 1

number of neutron = (mass number) - (atomic number)

a)
13 6C
number of neutron = 13 - 6
= 7
for 13 7N
number of neutron = 13-7
= 6
so, number of neutron is not same

b)
37 17Cl
number of neutron = 37-17
= 20
for 36 18Ar
number of neutron = 36-18
= 18
so, number of neutron is not same

c)
18 8O
number of neutron = 18 - 8
= 10
for 19 9F
number of neutron = 19-9
= 10
so, number of neutron is same

d)
6 3Li
number of neutron = 6-3
= 3
for 7 3Li
number of neutron = 7-3
= 4
so, number of neutron is not same

so,
only 18 8O and 19 9F has same number of neutron