Define $RQ$. What is its value for fats?

(N/A) Respiratory quotient $(RQ)$ or respiratory ratio is defined as the ratio of the volume of $CO_2$ evolved to the volume of $O_2$ consumed during respiration.
The value of $RQ$ depends on the type of respiratory substrate. For carbohydrates,the value is $1$.
For fats,the $RQ$ value is always less than $1$ because fats require more oxygen for complete oxidation compared to carbohydrates.
For example,in the respiration of tripalmitin (a fatty acid),$102$ molecules of $CO_2$ are evolved while $145$ molecules of $O_2$ are consumed. Thus,the $RQ$ value for tripalmitin is $102 / 145 = 0.7$.