QQuestion
Calculate:
(a) The percentage of phosphorus in the fertilizer super phosphate Ca(H2PO4)2 correct to 1 decimal point.
(b) Write the empirical formula of C8H18
[At. Wt. H=1, P=31, O=16, Ca=40]
✓Answer
(a) Formula mass of Ca(H₂PO₄)₂ = 40 + 2[2(1) + 31 + 4(16)] = 234.
Mass of phosphorus = 2 × 31 = 62.
\frac{62}{234}\times100=26.5\%(b) C₈H₁₈ = (C₄H₉)₂.
Empirical formula = C₄H₉.
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