WAEC - Chemistry (2018 - No. 41)
What is the relative molecular mass of a compound which has empirical formula \(CH_{2}O\)? [C= 12, H= 1, O= 16]
42
45
126
180
Explication
Molecular formula = (empirical formula x n)
where n= (1,2,3,...)
\(CH_{2}O = 12 + (2\times 1) + 16 = 30\)
Relative molecular mass = (30 x n)
From the options, only 180 is a multiple of 30, when n=6.