Question

# In preparation of sulphuric acid from sulphur dioxide in the lead chamber process. What substance is used as a catalyst?A) Manganese dioxideB) Vanadium pentoxideC) Nitric oxideD) Raney Nickel

Hint: We can write the reaction of conversion of sulphur dioxide to sulphuric acid. As mentioned it happens through the lead chamber process. A catalyst is used to speed up the reaction. The homogeneous catalyst will be used in the lead chamber process.

As mentioned it is used to prepare the sulphuric acid, and this reaction is an example of homogeneous catalysis. Homogeneous catalysis, in which all the reactants, products, and the catalyst used exists in the same phase whether it is liquid, solid, or gas phase. Thus, the given reaction occurs through the oxidation of sulphur dioxide; it means that it involves the use of oxygen.
We know that there is formation of intermediate products in the homogeneous catalysis.
Let us write the chemical reactions involving the formation of intermediate products.
The first reaction is

2NO (g) + O$_2$(g) $\rightarrow$ 2NO$_2$ (g)

The second reaction we have,

2SO$_2$ (g) + 2NO$_2$(g) $\rightarrow$ 2SO$_3$ (g) + 2NO(g)

Now, from the first reaction we get to know that the nitrogen dioxide acts as an intermediate compound; whereas in the second reaction with the help of nitrogen dioxide, it involves the formation of sulphur trioxide.
Thus, we can write the reaction i.e.

2SO$_2$ (g) + O$_2$(g) $\xrightarrow{NO(g)}$ 2SO$_3$ (g)

Therefore, the above reaction happens in the lead chamber process, and each exists in the gaseous phase.
In the last, we can conclude that nitric oxide is used as a catalyst.

Hence, the correct option is (C).

Note: Don’t get confused we have chosen the nitric oxide because the intermediate formed in the lead chamber process is nitrogen dioxide as shown. The lead chamber process doesn’t relate to the other catalysts mentioned in the options.