Question

Question
10 Calculate the percentage by mass of carbon in ethanol, C2H5OH.
(A, values: C = 12.0, H = 1.0, 0 = 16.0)​

Answer 1

Required Answer :

→ The percentage by mass of carbon in ethonal = 26.08 %

Given :

Formula of ethanol = C₂H₅OH

Value of the masses :-

• Carbon (C) = 12
• Hydrogen (H) = 1
• Oxygen (O) = 16

To find :

• Percentage by mass of carbon in ethanol

Solution :

Firstly, we shall calculate the mass of ethanol.

To calculate the mass, multiply the number of atoms present in the molecule of that particular atom by its mass number. And then add each atom, the resultant value will be the mass of the compound.

→ Mass of ethanol (C₂H₅OH) :-

→ 12 × 2 + 1 × 5 + 16 × 1 + 1 × 1

→ 24 + 5 + 16 + 1

→ 46

Hence, the mass of ethanol is 46

Now, calculating the percentage of carbon present is ethanol :-

→ Percentage mass of carbon = Mass of carbon/Mass of ethanol × 100

→ 12/46 × 100

[Cancelling by 2 ] :-

→ 6/23 × 100

→ 26.08

Therefore, the percentage by mass of carbon in ethonal = 26.08 %