Question

The R.Q. value of oxalic acid is
A. 1
B. 0.7
C. 4
D. $\infty$
E. 1.5

Answer 1

The R.Q. the value of any chemical compound is the respiratory quotient value of that compound. It helps in knowing the ratio of carbon dioxide molecules to the oxygen molecules evolved, and is used during its metabolism.

Complete answer:
All the compounds (complex), which we consume, are needed to be broken down into smaller or simple compounds because the body can get energy, and other products formed (during the breakdown of a compound) are either utilized or thrown out of the body. This breakdown of compounds into simpler forms in order to get energy is known as the metabolism.
The metabolism is essential for the body as the energy requirement of the body is fulfilled by the metabolic processes of the body only. The metabolism of the product is mediated by certain factors. The compounds which need to be broken down are broken with their reaction with the oxygen present inside the body. As a result, energy is produced which is utilized in doing various processes and along with energy carbon dioxide and water molecules are formed. The water is utilized in the body and the carbon dioxide is removed out of the body through respiration.
Now this ratio of carbon dioxide evolved and the oxygen consumed is known as the respiratory quotient. The equation for the metabolism of oxalic acid and calculation of its R.Q. value is as follows:
$2{(COOH)_2} + {O_2} \to 4C{O_2} + 2{H_2}O$
$R.Q. = \dfrac{CO_2 \, \text{Evolved}}{O_2 \, \text{Consumed}}$
$R.Q. = \dfrac{4}{1} = 4$

Hence, the correct answer is option (C).

Note: The respiratory quotient value is very helpful in knowing the type of substance consumed by any individual. If the R.Q. value of a substance is higher then, it signifies that a high amount of energy is produced with less consumption of oxygen, whereas the lower R.Q. value signifies higher consumption of oxygen and releasing lesser energy.