Question

State true or false. The thermal dissociation reaction is not reversible.

Answer 1

Thermal dissociation is defined as the reaction in which a substance undergoes dissociation or in other words breaks-down into simpler substances at high temperatures.

Complete answer:
As we know what thermal dissociation means let’s know about the reversible reactions these are the type of the reactions which once converted into products can easily form back into reactants, and the thermal dissociation is a kind of reversible reactions as the products can again form into reactants one of the examples is: Calcium carbonate under high temperature or heat breaking down into Calcium oxide and carbon dioxide is reversible and is denoted by an arrow as shown in the reaction:
$CaC{O_3}\; \rightleftarrows CaO{\text{ }} + {\text{ }}C{O_2}$
Hence, the correct answer is False, that the thermal dissociation reaction is not reversible, as the above statements state that thermal decomposition is a reversible reaction.

Additional Information: The thermal dissociation is also called as thermal decomposition or thermolysis and there is another term linked to it and that’s decomposition temperature it is the temperature when a substance splits into two or more substances, and the decomposition temperature from the studies is found to be maximum for carbon monoxide at $3870$ degree Celsius, and when water is heated to a temperature of $2000$ degree Celsius, a small percentage of it will decompose into $O{H^ - }$, monatomic oxygen, monatomic hydrogen, ${O_2}$, and ${H_2}$

Note: The energy for $4s$ is less than $3d$ because the overall $\left( {n + l} \right)$ value is less for $4s$ than the $3d$, now the value of $l$ means the value of sub-shells; $s,{\text{ }}p,{\text{ }}d$and $f$are $0,{\text{ }}1,{\text{ }}2,{\text{ }}3$ respectively and for $4s$ the $\left( {n + l} \right)$ value comes out to be $4 + 0{\text{ }} = {\text{ }}4$ and for $3d$ is $3 + 2{\text{ }} = {\text{ }}5.$