Complete combustion of $1.80 g$ of an oxygen containing compound $\left( C _{ x } H _{ y } O _{2}\right)$ gave $2.64 g$ of $CO _{2}$ and $1.08 g$ of $H _{2} O$. The percentage of oxygen in the organic compound is:
- 51.63
- 63.53
- 53.33
- 50.33
The Correct Option is C
Solution and Explanation
To find the percentage of oxygen in the compound \(C_{x}H_{y}O_{2}\) that upon combustion produces \(2.64 \, \text{g}\) of \(CO_{2}\) and \(1.08 \, \text{g}\) of \(H_{2}O\), follow these steps:
- Calculate the moles of \(CO_{2}\) produced:
\(\text{Molar mass of } CO_{2} = 44 \, \text{g/mol}\)
\(\text{Moles of } CO_{2} = \frac{2.64 \, \text{g}}{44 \, \text{g/mol}} = 0.06 \, \text{mol}\)
- Calculate the moles of carbon present:
Each mole of \(CO_{2}\) contains 1 mole of carbon, so:
\(\text{Moles of carbon} = 0.06 \, \text{mol}\)
- Calculate the mass of carbon:
\(\text{Mass of carbon} = 0.06 \, \text{mol} \times 12 \, \text{g/mol} = 0.72 \, \text{g}\)
- Calculate the moles of \(H_{2}O\) produced:
\(\text{Molar mass of } H_{2}O = 18 \, \text{g/mol}\)
\(\text{Moles of } H_{2}O = \frac{1.08 \, \text{g}}{18 \, \text{g/mol}} = 0.06 \, \text{mol}\)
- Calculate the moles of hydrogen present:
Each mole of \(H_{2}O\) contains 2 moles of hydrogen, so:
\(\text{Moles of hydrogen} = 0.06 \, \text{mol} \times 2 = 0.12 \, \text{mol}\)
- Calculate the mass of hydrogen:
\(\text{Mass of hydrogen} = 0.12 \, \text{mol} \times 1 \, \text{g/mol} = 0.12 \, \text{g}\)
- Determine the mass of oxygen in the compound:
\(\text{Total mass of compound} = 1.80 \, \text{g}\)
\(\text{Mass of oxygen} = 1.80 \, \text{g} - (0.72 \, \text{g} + 0.12 \, \text{g}) = 0.96 \, \text{g}\)
- Calculate the percentage of oxygen:
\(\text{Percentage of oxygen} = \left( \frac{0.96 \, \text{g}}{1.80 \, \text{g}} \right) \times 100 = 53.33\%\)
Therefore, the percentage of oxygen in the organic compound is 53.33%.
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Concepts Used:
Organic Chemistry - Some Basic Principles and Techniques
Organic Chemistry is a subset of chemistry dealing with compounds of carbon. Therefore, we can say that Organic chemistry is the chemistry of carbon compounds and is 200-225 years old. Carbon forms bond with itself to form long chains of hydrocarbons, e.g.CH4, methane and CH3-CH3 ethane. Carbon has the ability to form carbon-carbon bonds quite elaborately. Polymers like polyethylene is a linear chain where hundreds of CH2 are linked together.
Read Also: Organic Compounds
Importance of Organic Chemistry:
Organic chemistry is applicable in a variety of areas including-
- Medicines: Example- Aspirin which is a headache medicine and Ibuprofen is a painkiller, both are organic compounds. Other examples include paracetamol.
- Food: Example- Starch which is a carbohydrate is an organic compound and a constituent of rice and other grains. It is the source of energy.
- Clothing: Example- Nylon, Polyester and Cotton are forms of organic compounds.
- Fuels: Examples- Gasoline, Petrol and Diesel are organic compounds used in the automobile industry at large.