Q. Consider the following balanced chemical reaction
$3A+4B+5C \rightarrow 2D$
If 7 moles of A, 9 moles of B and 8 moles of C are given initially, the mole fraction of D present after completion of reaction is

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0.24

0.65

0.40

0.08

Solution:

$ & 3A & + & 4B & + & 5C & \rightarrow & 2D \\ Moles \, & 7 & & 9 & & 8 & & \\ Afterreaction: & 2.2 & & 2.6 & & - & & 3.2$
$\therefore $ C is limiting reagent
Mole fraction of $D= \, 0.4.$

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