Question

Nahco3 is the active ingredient in baking soda. how many grams of oxygen are in 0.72 g of nahco3?

Answer 1

M (O) = M x n

M (O) = 16g/mol

n (O) = 3 x n (NaHCO3)

n (NaHCO3) = m/M

m (NaHCO3) = 0.72g

M (NaHCO3) = 23 + 1 + 14 + 16 x 3 = 86g/mol

n (NaHCO3) = 0.72/86 = 0.008372mol

n (O) = 3 x 0.008372 = 0.02512

m (O) = 16 x 0.02512 = 0.402g