Calculate the relative molecular mass of Limestone CaCO3, (Ca = 40, C =12, O = 16)
56
100
76
90
Correct answer is B
One molecule of CaCO has 1Ca, 1C and 30 atom relative molecular mass of CaCO3
1 × Ar of Ca +1 × Ar of C +3 × Ar of O
(1 × 40 + 1 × 12 + 3 × 1)
40 + 12 + 48
=100
Option A,C and D will not give 100