Question

120 gram of an organic compound on combustion analysis gives 330 gram of carbondioxide and 270 gram of water. % by mass of C and H in organic compound is:

(1) 50% C and 50% H
(2) 60% C and 40% H
(3) 80% C and 20% H
(4) 75% C and 25% H

Answer 1

The percent by mass of carbon and hydrogen in the organic compound is 75% C and 25% H. Option number 4 is correct.

Step-by-step explanation:

The percent by mass of carbon and hydrogen in the organic compound can be calculated using the information from the combustion analysis.

From the given information, 120 grams of the compound produces 330 grams of carbon dioxide and 270 grams of water.

To find the percent by mass of carbon and hydrogen, you need to calculate the mass of carbon and hydrogen in the original compound and divide it by the total mass of the compound.

Let's calculate the percent by mass of carbon and hydrogen:

1. Mass of carbon in the compound: 330g CO2 x (12.01g C / 44.01g CO2) = 90g C
2. Mass of hydrogen in the compound: 270g H2O x (2.016g H / 18.016g H2O) = 30g H
3. Percent by mass of carbon: (90g C / 120g organic compound) x 100% = 75%
4. Percent by mass of hydrogen: (30g H / 120g organic compound) x 100% = 25%

Therefore, the percent by mass of carbon and hydrogen in the organic compound is 75% C and 25% H.