Question

Calculate no. of moles 1)392g of sulphuric acid 2) Avogadro no. of molecules of oxygen 3) 9g of Alluminium r) 7.9mg of calcium.

Answer 1

1) n = m / M

= 392 / 98

= 4 moles

3) 9 g of aluminium

M = 27

n = m / M

= 9 / 27

0.33 moles


4) 7. 9 mg of Calcium

1 g = 1000mg

0.0079 g

M = 40

n = m / M = 0. 0079 / 40

0. 00019 moles


Thanks