Question

Nitrogen monoxide is a colorless gas that turns reddish-brown when mixed with air. What is responsible for the color change? (a) What is the chemical composition of liquefied nitrogen(IV) oxide? (b) What is the principal use of liquefied nitrogen(IV) oxide? Nitrous acid is unstable toward disproportionation. Write a balanced equation for the disproportionation reaction. Decide the oxidation state of nitrogen in the reactant and products.

Answer 1

When nitrogen oxide is mixed with air it forms NO2(liquid) which is reddish brown in color . Thus formation of nitrogen(IV)oxide is responsible for color change of NO as ;

2NO(g) + O2(g) >>>>>> 2NO2(l)

Colorless reddish brown

  

a) Nitrogen(IV) oxide is made up of 1 nitrogen and 2 oxygen atoms in it .

b) Liquified NO2 is used a rocket fuel .

c) Disproportionation reaction of nitrous acid(HNO2) as ;

3HNO2 >>>disproportionates>>>> HNO3 + 2NO + H2O

Oxidantion state of N in HNO2(reactant) is +3

Oxidation state of N in NO(product) is +2

and HNO3(product) is +5

The reactions in which same element undergoes reduction and oxidation at the same time is called disproportionation reaction.