Question

How much positive and negative charge in these in a cup of Water

Answer 1

Solution :

Suppose the cup contains 250 cc of water ( H₂O )

→ Mass of 250 cm³ of water = 250 g

→ Molecular weight of water = 2 + 16 = 18

→ Numbers of molecules in 18 g of water = 6.023 x 10²³

→ Numbers of molecules in 250 g of water = ( 6.023 x 10²³ x 250 ) / 18

As each molecule of water contain 10 electrons , therefore , total number of electron ,

→ n = ( 10 x 6.023 x 10²³ x 250 ) / 18

→ n = 8.365 x 10²⁵

As q = ne

→ q = 8.365 x 10²⁵ x 1.6 x 10⁻¹⁹ C

→ q = 1.338 x 10⁷ C