Verified Solution • 2025–26 Session moderate

QJEEM25Chd6fa: JEE Main 2025 Chemistry - Class 11 JEEM25Chd6fa Solution: When 81.0 g of aluminium is allowed to react with 128.0 g of…

When 81.0 g of aluminium is allowed to react with 128.0 g of oxygen gas, the mass of aluminium oxide produced in grams is ________ . (Nearest integer)

Given :

Molar mass of Al is 27.0 g mol−127.0 \mathrm{~g} \mathrm{~mol}^{-1}

Molar mass of O is 16.0 g mol−116.0 \mathrm{~g} \mathrm{~mol}^{-1}

Step-by-Step Verified Solution

4Al+3O2⟶2Al2O34 \mathrm{Al}+3 \mathrm{O}_2 \longrightarrow 2 \mathrm{Al}_2 \mathrm{O}_3

amp;8127=3 mole 12832=4 mole amp; Limiting reagent amp;∴ mole of Al2O3 formed =12×3 mole amp;∴ wt. of Al2O3 formed =32×102amp;=153gm\begin{aligned}& \frac{81}{27}=3 \text { mole } \frac{128}{32}=4 \text { mole } \\& \text { Limiting reagent } \\& \therefore \text { mole of } \mathrm{Al}_2 \mathrm{O}_3 \text { formed }=\frac{1}{2} \times 3 \text { mole } \\& \therefore \text { wt. of } \mathrm{Al}_2 \mathrm{O}_3 \text { formed }=\frac{3}{2} \times 102 \\& =153 \mathrm{gm}\end{aligned}

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