Question

Compute the number of sodium ions present in 5.85g of sodium chloride. (Atomic mass of
sodium =23u and of chorine =35.5u), No=6.022X1023 per mole

Answer 1

The total atomic mass of Sodium Chloride is :

35.5 + 23 = 58.5 g

From the given mass the mass of Sodium is :

23/58.5 × 5.85 = 2.3 g

The moles of Sodium are :

Moles = mass / Atomic mass.

Moles = 2.3/23 = 0.1 moles

Now ,

1 mole = 6.022 × 10²³ ions

The number of Sodium ions in 5.85 g Sodium Chloride is thus :

0.1 × 6.022 × 10²³ = 6.022 × 10²² Ions