Question

write the chemical formula for the following compounds and find the ratio by mass of the combining elements in each one of them (N=14u,H=10u,C=12u,O=16u,S=32u (a) methene (b) carbon dioxide (c) hydrogen sulphide

Answer 1

see attachment....hope it will helps..

Answer 2

a) Methane consists of 2 elements : Carbon and hydrogen.
Formula : CH₄
Mass of Carbon = 12 u
Mass of hydrogen = 1 u
Ratio of mass of Carbon to the mass of hydrogen = 12 : 1 = 3 : 1
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b)Carbon dioxide
Carbon dioxide consists of 2 elements : Carbon and Oxygen.There is 1 atom of Carbon and 2 atom of Oxygen.
Formula : CO₂
Mass of Carbon = 12 u
Mass of Oxygen = 16 × 2 = 32 u
Ratio of mass of Carbon to the mass of Oxygen = 12 : 32 = 3 : 8
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c)Hydrogen sulphide
Hydrogen sulphide consists of Hydrogen and sulphur .There are two atoms of Hydrogen and 1 atom of sulphur.
Formula : H₂S
Mass of Hydrogen = 1 × 2 = 2 u
Mass of sulphur = 32 u
Ratio of mass of hydrogen to the mass of sulphur = 2 : 32 = 1 : 16