Question

Calculate the formula mass of sodium carbonate dehydrate (Na2CO3
–10H2O)

Answer 1

286u

Explanation:

We know that,

Atomic mass of Na = 23, C = 12, O = 16, H = 1

Formula mass of Na₂CO₃ = (2 × 23) + 12 + ( 3 × 16)

                                          = 106

Formula mass of 10 H₂O = (20 × 1) +( 10 × 16)

                                         = 180u

Formula mass of Na₂CO₃.10H₂O = 106 + 180

                                                      = 286u