Question

What is the no. Of water molecules contained in a drop of water weighing 0.06g?

Answer 1

Given,

=> H20 = 2+16 g = 18 g

No. of Moles = Given mass/Molar mass

=> No. of Moles = 0.06/18 g

=> No. of Moles =0.0033

Again,


No. of Particles or Molecules = No. of Moles x Avogadro's No.

=> No. of Particles = 0.0033 x 6.022 x 10^23

=> No. of Particles =1.98 x 10^21



Be Brainly

Answer 2

Molecular weight of water

H = 1

O = 16

Water = H₂O

= > 1 × 2 + 16

= > 2 + 16

= > 18

Find moles

Hence 18 g of water will have 1 mole.

1 g of water has 1 / 18 moles .

0.06 g of water has 1 / 18 × 0.06 moles

= > 0.06 g of water has 0.06 / 18 moles

                                     = 6 / 1800

                                     = 1 / 300

                                     = 0.0033

Find molecules

1 mole has 6.023 × 10²³ molecules .

0.033 moles will have 0.0033 × 6.023 × 10²³ molecules .

                                   = 0.01987  × 10²³ molecules

                                   = 0.0199 × 10²³ molecules

                                   = 1.99 × 10²¹ molecules .

ANSWER :

The number of molecules is 1.99 × 10²¹ .