A0.1153-gram sample of a pure hydrocarbon was burned in a c-h combustion train to produce 0.3986 gram of co2and 0.0578 gram of h2o. determine the masses of c and h in the sample and the percentages of these elements in this hydrocarbon.

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:

where, 'x' and 'y' are the subscripts of carbon and hydrogen respectively.

We are given:

Mass of

Mass of

Mass of sample = 0.1153 g

We know that:

Molar mass of carbon dioxide = 44 g/mol

Molar mass of water = 18 g/mol

In 44g of carbon dioxide, 12 g of carbon is contained.

So, in 0.3986 g of carbon dioxide, of carbon will be contained.

In 18g of water, 2 g of hydrogen is contained.

So, in 0.0578 g of water, of hydrogen will be contained.

To calculate the percentage composition of a substance in sample, we use the equation:

     ......(1)

Mass of sample = 0.1153 g

Mass of carbon = 0.1087 g

Putting values in equation 1, we get:

Mass of sample = 0.1153 g

Mass of hydrogen = 0.0066 g

Putting values in equation 1, we get:

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.

c. 75.7

i think that is the right

the answer is 303.15 or 303