$2 {~K}_{2} {Cr}_{2} {O}_{7}+8 {H}_{2} {SO}_{4}+3 {C}_{2} {H}_{6} {O} \rightarrow 2 {Cr}_{2}\left({SO}_{4}\right)_{3}+$
$3 {C}_{2} {H}_{4} {O}_{2}+2 {~K}_{2} {SO}_{4}+11 {H}_{2} {O}$
જો ${Cr}_{2}\left({SO}_{4}\right)_{3}$નો દેખાવનો દર $2.67 \,{~mol}$ $\min ^{-1}$ ચોક્કસ સમયે, ${C}_{2} {H}_{6} {O}$નો એક જ સમયે ગાયબ થવાનો દર $....$ ${mol}\, {min}^{-1}$ છે. (નજીકના પૂર્ણાંકમાં)
$=\left(\frac{\text { Rate of appearance of } {Cr}_{2}\left({SO}_{4}\right)_{3}}{2}\right)$
$\Rightarrow\left(\frac{2.67 {~mol} / {min} \times 3}{2}\right)=$ rate of disappearance of ${C}_{2} {H}_{6} {O} .$
$\Rightarrow$ Rate of disappearance of ${C}_{2} {H}_{6} {O}=4.005$ ${~mol} / {min}$
(આપેલું છે$: \ln 10=2.3, R =8.3 \,J\, K ^{-1} \,mol ^{-1}, \log 2=0.30$ )