Please answer my both questions

Dear student,
5) The percentage composition of Cu in CuSO₄ = mass of Cu / mass of CuSO₄ x 100
Molecular mass of CuSO₄ = 63.5 + 32 + (4x16)
                                             (Cu)    (S)     (O)
                                          = 159.5
Percentage composition of Cu = 63.5 / 159.5 x 100
                                                 = 39.8 %


6) The percentage composition of any element in a compound = mass of element/mass of compound x 100
Given data:
Mass of sulphuric acid = 4.9 g
Mass of hydrogen = 0.1 g
Mass of sulphur=1.6 g
Mass of oxygen = 3.2 g

Now percentage composition of each element will be:
The percentage composition of hydrogen = 0.1/4.9  x 100 = 2.04%
The percentage composition of sulphur = 1.6/4.9  x 100 = 32.6%
​​​​​​​The percentage composition of oxygen= 3.2/4.9  x 100 = 65.3%


​​​​​​​Hope this information will clear your doubts about topic.

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