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QJEEM24Ch8a36: JEE Main 2024 Chemistry - Class 11 JEEM24Ch8a36 Solution: Mass of methane required to produce of after complete…

Mass of methane required to produce 22 g22 \mathrm{~g} of CO2\mathrm{CO}_2 after complete combustion is _______ g.

(Given Molar mass in g mol-1 C=12.0\mathrm{C}=12.0 , H=1.0\mathrm{H}=1.0 , O=16.0)\mathrm{O}=16.0)

Step-by-Step Verified Solution

To solve this problem, we can use stoichiometry. First, we need to write down the balanced chemical equation for the complete combustion of methane ( CH4\mathrm{CH}_4 ).

The balanced equation for combustion of methane is:

CH4+2O2→CO2+2H2O\mathrm{CH}_4+2 \mathrm{O}_2 \rightarrow \mathrm{CO}_2+2 \mathrm{H}_2 \mathrm{O}

This equation tells us that one mole of methane reacts with two moles of oxygen to produce one mole of carbon dioxide and two moles of water.

Next, we should find the molar mass of methane ( CH4\mathrm{CH}_4 ) using the given molar masses:

Molar mass of CH4\mathrm{CH}_4 = molar mass of C + 4 * molar mass of H

Molar mass of CH4\mathrm{CH}_4 = 12.0 g/mol12.0\ \mathrm{g/mol} (for C) + 4∗1.0 g/mol4 * 1.0\ \mathrm{g/mol} (for H)

Molar mass of CH4\mathrm{CH}_4 = 12.0 g/mol+4.0 g/mol12.0\ \mathrm{g/mol} + 4.0\ \mathrm{g/mol}

Molar mass of CH4\mathrm{CH}_4 = 16.0 g/mol16.0\ \mathrm{g/mol}

Now, to determine the mass of methane required to produce 22 g22\ \mathrm{g} of CO2\mathrm{CO}_2 , we should find out how many moles of CO2\mathrm{CO}_2 there are in 22 g22\ \mathrm{g} and use the mole ratio from the balanced equation to find the moles of methane required.

Moles of CO2\mathrm{CO}_2 = mass of CO2\mathrm{CO}_2 / molar mass of CO2\mathrm{CO}_2

Molar mass of CO2\mathrm{CO}_2 = molar mass of C + 2 * molar mass of O

Molar mass of CO2\mathrm{CO}_2 = 12.0 g/mol12.0\ \mathrm{g/mol} + 2∗16.0 g/mol2 * 16.0\ \mathrm{g/mol}

Molar mass of CO2\mathrm{CO}_2 = 12.0 g/mol+32.0 g/mol12.0\ \mathrm{g/mol} + 32.0\ \mathrm{g/mol}

Molar mass of CO2\mathrm{CO}_2 = 44.0 g/mol44.0\ \mathrm{g/mol}

Moles of CO2\mathrm{CO}_2 = 22 g44.0 g/mol\frac{22\ \mathrm{g}}{44.0\ \mathrm{g/mol}}

Moles of CO2\mathrm{CO}_2 = 0.5 moles0.5\ \mathrm{moles}

We will use the stoichiometric ratio from the balanced chemical equation to find the moles of CH4\mathrm{CH}_4 required to produce 0.5 moles0.5\ \mathrm{moles} of CO2\mathrm{CO}_2 :

1 mole of CH4:1 mole of CO21\ \mathrm{mole\ of\ CH}_4 : 1\ \mathrm{mole\ of\ CO}_2

This means that we also require 0.5 moles0.5\ \mathrm{moles} of CH4\mathrm{CH}_4 .

Finally, we need to convert moles of methane to grams to find the mass:

Mass of CH4\mathrm{CH}_4 = moles of CH4\mathrm{CH}_4 * molar mass of CH4\mathrm{CH}_4

Mass of CH4\mathrm{CH}_4 = 0.5 moles∗16.0 g/mol0.5\ \mathrm{moles} * 16.0\ \mathrm{g/mol}

Mass of CH4\mathrm{CH}_4 = 8.0 g8.0\ \mathrm{g}

Therefore, 8.0 g8.0\ \mathrm{g} of methane is required to produce 22 g22\ \mathrm{g} of carbon dioxide after complete combustion.

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