Easy INTEGER +4 / -1 PYQ · JEE Mains 2020

The minimum number of moles of O2 required for complete combustion of 1 mole of propane and 2 moles of butane is _____.

Answer (integer) 18

Solution

C<sub>3</sub>H<sub>8</sub>(g) + 5O<sub>2</sub>(g) $\to$ 3CO<sub>2</sub>(g) + 4H<sub>2</sub>O(l) <br><br>C<sub>4</sub>H<sub>10</sub>(g) + ${{13} \over 2}$O<sub>2</sub>(g) $\to$ 4CO<sub>2</sub>(g) + 5H<sub>2</sub>O(l) <br><br>$\therefore$ No. of moles of O<sub>2</sub> required to oxidise 1 mole of propane = 5 <br><br>$\therefore$ No. of moles of O<sub>2</sub> required to oxidise 1 mole of butane = ${{13} \over 2}$ <br><br>So, No. of moles of O<sub>2</sub> required to oxidise 1 mole of <br><br/>propane and 2 moles of butane = 5 + 2 $\times$ ${{13} \over 2}$ = 18

About this question

Subject: Chemistry · Chapter: Hydrocarbons · Topic: Alkanes

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