Question

Given, \[HOOC - {(C{H_2})_5} - COOH\xrightarrow{{Ca{{(OH)}_2}/\vartriangle }}X\] .What is the compound X ?
A.

B.

C.

D.

Answer 1

Hint: Carboxylic acids undergo various types of chemical reactions like addition,substitution, decomposition etc.The rate and products formed in these reactions depend on factors like a catalyst and other reactants involved.

Complete answer:
An organic acid that has one or more carboxyl groups ($ - COOH$) attached to it can be termed as Carboxylic acid. They can undergo a variety of chemical reactions whose end products depend on the catalysts and reactants involved.
In the above chemical reaction, we have started the reaction with Heptanedioic acid which is also known by its common name as Pimelic acid. The derivatives of pimelic acid help in the biosynthesis of an amino acid named lysine. It also acts as a precursor to many polyesters and polyamides.
Since pimelic acid does not undergo thermal decomposition readily, a catalyst Calcium hydroxide ($Ca{(OH)_2}$ ) is introduced. Calcium hydroxide is a well-known reducing agent. The general chemical reaction of thermal decomposition involving a substituted carboxylic acid is given as.
$HOOC - R - COOH\xrightarrow[\vartriangle ]{{Ca{{(OH)}_2}}}R' = O + C{O_2} + {H_2}O$
Where R’ is a saturated cyclic ketone having one less carbon atom than it’s a precursor. Similarly generating the chemical reaction we get.

The byproducts will be $C{O_2} + {H_2}O$ .The main product formed is known as cyclohexanone. It’s a colorless liquid.

Hence from our analysis, we know that a correct option is an option (a).

Note:
Cyclohexanone looks like a colorless liquid. However, over a period of time, it gains a pale yellow color. Its odour is reminiscent to that of acetone. It’s widely used in the pharmaceutical industry, pesticide manufacturing and plastic industry.It’s an excellent solvent for organic phosphorus. It is also used for the manufacturing of herbicides and antihistamines.