Question

Calculate
i) the volume of one molecule of water
ii) the radius of water molecule assuming the molecule to be spherical.
(Given that density of water is 1 g/mL)​

Answer 1

Answer:

As you know, the density of water is 1g/cm

2

and the molecular weight of water is 18g/mol, it contains 6.023×10

2

3 molecules of it.

first of all, we have to find the volume of water=

density

mass

=

1g/cm

3

18g

=18cm

3

hence the volume of water=18cm

3

=18×10

−6

m

3

1 mole of water=6.023×10

23

molecules

the volume of 6.023×10

23

molecules of water=1.8×10

−5

m

3

the volume of 1 molecule of water=

6.023

1.8

×10

−

5

−

23

=0.2988×10

28

m

3

b.) let radius of water molecules is r.

then, the volume of 1 molecule of water=

3

4

πr

3

3

4

πr

3

=0.2988×10

−28

m

3

r

3

=0.2988×

4π

3

×10

−28

r=0.1925×10

−9

m=0.1925 nm

Answer 2

Explanation:

1. Volume of 1 molecule of water = 2.989 × 10-23 ≈ 3 × 10-23.
2. r = 0.1925 × 10⁻⁹ m = 0.1925 nm