Find the ratio by mass of the combining elements in the following compounds. (You may use Appendix-III) (a) CaCO3 (d) C2H5OH (b) MgCl2 (e) NH3 (c) H2SO4 (f) Ca(OH)2
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
- CaCO3 Ca: C : O × 3
40 : 12 : 16 × 3
40: 12 : 48
10 : 3 : 12
- MgCl2 Mg : Cl × 2 24: 5 × 2
24: 71
- H2SO4
H x 2 : S : O × 4 2: 32 : 16 × 4
2 : 32 : 64
1: 16: 32
- C2H5OH
C × 2 : H × 6 : O 12 × 2 : 1 × 6 : 16
24 : 6 : 16
12 : 3 : 8
- NH3 N : H × 3 14 : 1 × 3
14: 3
- Ca(OH)2
Ca : O × 2 : H × 2 40 : 16 × 2 : 1 × 2
40 : 32 : 2
20 : 16 : 1
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