Respuesta :
Answer: The mass of carbon and hydrogen in the sample is 0.1087 g and 0.0066 g respectively and the percentage composition of carbon and hydrogen in the sample is 94.27 % and 5.72 % respectively.
Explanation:
The chemical equation for the combustion of hydrocarbon having carbon and hydrogen follows:
[tex]C_xH_y+O_2\rightarrow CO_2+H_2O[/tex]
where, 'x' and 'y' are the subscripts of carbon and hydrogen respectively.
We are given:
Mass of [tex]CO_2=0.3986g[/tex]
Mass of [tex]H_2O=0.0578g[/tex]
Mass of sample = 0.1153 g
We know that:
Molar mass of carbon dioxide = 44 g/mol
Molar mass of water = 18 g/mol
- For calculating the mass of carbon:
In 44g of carbon dioxide, 12 g of carbon is contained.
So, in 0.3986 g of carbon dioxide, [tex]\frac{12}{44}\times 0.3986=0.1087g[/tex] of carbon will be contained.
- For calculating the mass of hydrogen:
In 18g of water, 2 g of hydrogen is contained.
So, in 0.0578 g of water, [tex]\frac{2}{18}\times 0.0578=0.0066g[/tex] of hydrogen will be contained.
To calculate the percentage composition of a substance in sample, we use the equation:
[tex]\%\text{ composition of substance}=\frac{\text{Mass of substance}}{\text{Mass of sample}}\times 100[/tex] ......(1)
- For Carbon:
Mass of sample = 0.1153 g
Mass of carbon = 0.1087 g
Putting values in equation 1, we get:
[tex]\%\text{ composition of carbon}=\frac{0.1087g}{0.1153g}\times 100=94.27\%[/tex]
- For Hydrogen:
Mass of sample = 0.1153 g
Mass of hydrogen = 0.0066 g
Putting values in equation 1, we get:
[tex]\%\text{ composition of hydrogen}=\frac{0.0066g}{0.1153g}\times 100=5.72\%[/tex]
Hence, the mass of carbon and hydrogen in the sample is 0.1087 g and 0.0066 g respectively and the percentage composition of carbon and hydrogen in the sample is 94.27 % and 5.72 % respectively.
