In a combustion experiment, 32.05 mg of alcohol, R-OH produced 44.01mg of carbondioxide and 36.04mg of water calculate the mass of carbon hydrogen and oxygen and their percent in alcohol
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To calculate the mass of carbon, hydrogen, and oxygen in the alcohol, we need to use the information given in the combustion experiment.
Step 1: Calculate the mass of carbon dioxide (CO2) produced.
From the experiment, it is given that 32.05 mg of alcohol (R-OH) produced 44.01 mg of carbon dioxide (CO2).
So the mass of carbon in CO2 = mass of CO2 produced = 44.01 mg.
Carbon dioxide (CO2) has one carbon atom (C) and two oxygen atoms (O2). The atomic mass of carbon (C) is 12.01 g/mol, and the atomic mass of oxygen (O) is 16.00 g/mol.
Therefore, the mass of carbon (C) in CO2 can be calculated using the formula:
Mass of carbon (C) = (mass of CO2 produced) * (mass of carbon (C) / molar mass of CO2)
= 44.01 mg * (12.01 g/mol / 44.01 g/mol)
= (44.01 mg * 12.01 g/mol) / 44.01 g/mol
= 12.01 mg.
Step 2: Calculate the mass of water (H2O) produced.
From the experiment, it is given that 32.05 mg of alcohol (R-OH) produced 36.04 mg of water (H2O).
So the mass of water in H2O = mass of H2O produced = 36.04 mg.
Water (H2O) has two hydrogen atoms (H) and one oxygen atom (O). The atomic mass of hydrogen (H) is 1.01 g/mol, and the atomic mass of oxygen (O) is 16.00 g/mol.
Therefore, the mass of hydrogen (H) in H2O can be calculated using the formula:
Mass of hydrogen (H) = (mass of H2O produced) * (mass of hydrogen (H) / molar mass of H2O)
= 36.04 mg * (2 * 1.01 g/mol / 36.04 g/mol)
= (36.04 mg * 2.02 g/mol) / 36.04 g/mol
= 2.02 mg.
Step 3: Calculate the mass of oxygen (O) in the alcohol.
The mass of oxygen (O) can be calculated by subtracting the sum of the mass of carbon (C) and hydrogen (H) from the mass of alcohol.
Mass of oxygen (O) = mass of alcohol - (mass of carbon (C) + mass of hydrogen (H))
= 32.05 mg - (12.01 mg + 2.02 mg)
= 17.02 mg.
Step 4: Calculate the percent composition of carbon, hydrogen, and oxygen in the alcohol.
The percent composition of an element in a compound can be calculated using the formula:
Percent composition of an element = (mass of element / total mass of compound) * 100
Percent composition of carbon in alcohol (C) = (mass of carbon (C) / mass of alcohol) * 100
= (12.01 mg / 32.05 mg) * 100
= 37.46 %
Percent composition of hydrogen in alcohol (H) = (mass of hydrogen (H) / mass of alcohol) * 100
= (2.02 mg / 32.05 mg) * 100
= 6.31 %
Percent composition of oxygen in alcohol (O) = (mass of oxygen (O) / mass of alcohol) * 100
= (17.02 mg / 32.05 mg) * 100
= 53.23 %
Therefore, the mass of carbon, hydrogen, and oxygen in the alcohol are approximately:
- Carbon (C): 12.01 mg
- Hydrogen (H): 2.02 mg
- Oxygen (O): 17.02 mg
And their percent composition in the alcohol is approximately:
- Carbon (C): 37.46 %
- Hydrogen (H): 6.31 %
- Oxygen (O): 53.23 %