First Order Reaction:
A first-order reaction is a type of chemical reaction in which the rate of reaction is directly proportional to the concentration of only one reactant. The reaction follows first-order kinetics, which means that the rate equation can be expressed as:

Rate = k[A]

Where:
- Rate is the rate of the reaction
- k is the rate constant
- [A] is the concentration of the reactant A

The given options are:
a) Acid catalysed hydrolysis of ethyl acetate
b) Formation and dissociation of ozone
c) Inversion of cane sugar
d) Decomposition of nitrogen pentoxide

Explanation:
To determine which reaction is an example of a first-order reaction, we need to analyze the rate equation and identify the reactant concentration that affects the rate of the reaction.

a) Acid catalysed hydrolysis of ethyl acetate:
The hydrolysis of ethyl acetate is a second-order reaction because it involves the simultaneous collision of two molecules (ethyl acetate and water). Therefore, it does not follow first-order kinetics.

b) Formation and dissociation of ozone:
The formation and dissociation of ozone involve multiple steps and the concentration of ozone does not directly affect the rate of the reaction. Hence, it is not a first-order reaction.

c) Inversion of cane sugar:
The inversion of cane sugar is a hydrolysis reaction that occurs in the presence of an acid or an enzyme. It follows pseudo-first-order kinetics because the concentration of the acid or enzyme is much higher than the concentration of the cane sugar. Therefore, it is not a first-order reaction.

d) Decomposition of nitrogen pentoxide:
The decomposition of nitrogen pentoxide is a first-order reaction. The rate of reaction is directly proportional to the concentration of nitrogen pentoxide. As the concentration of nitrogen pentoxide decreases, the rate of reaction also decreases. Therefore, option d is the correct answer.

In conclusion, among the given options, the decomposition of nitrogen pentoxide is an example of a first-order reaction.