Medium INTEGER +4 / -1 PYQ · JEE Mains 2021

The reaction that occurs in a breath analyser, a device used to determine the alcohol level in a person's blood stream is

$$2{K_2}C{r_2}{O_7} + 8{H_2}S{O_4} + 3{C_2}{H_6}O \to 2C{r_2}{(S{O_4})_3} + 3{C_2}{H_4}{O_2} + 2{K_2}S{O_4} + 11{H_2}O$$

If the rate of appearance of Cr2(SO4)3 is 2.67 mol min$-$1 at a particular time, the rate of disappearance of C2H6O at the same time is _____________ mol min$-$1. (Nearest integer)

Answer (integer) 4

Solution

$\left( {{{Rate\,of\,disappearance\,of\,{C_2}{H_6}O} \over 3}} \right)$<br><br>$= \left( {{{Rate\,of\,disappearance\,of\,C{r_2}{{(S{O_4})}_3}} \over 2}} \right)$<br><br>$\Rightarrow \left( {{{2.67\,mol/\min \, \times 3} \over 2}} \right) =$ rate of disappearance of C<sub>2</sub>H<sub>6</sub>O.<br><br>$\Rightarrow$ Rate of disappearance of C<sub>2</sub>H<sub>6</sub>O = 4.005 mol/min.

About this question

Subject: Chemistry · Chapter: Chemical Kinetics · Topic: Rate of Reaction

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