- Why is diluted sulphuric acid [H2SO4] added while preparing standard Mohr’s solution?
It is added to prevent hydrolysis of ferrous salt.
- Can you use hydrochloric acid [HCl] or nitric acid [HNO3] in potassium permanganate [KMNO4] titrations? Why?
No. HNO3 is itself an oxidising agent whereas HCl being oxidisable to chlorine and hydrogen consumes permanganate.
- What is the oxidation number of manganese in potassium permanganate [KMNO4] ?
Oxidation number of manganese in KMNO4 is 7.
- Why are hot solutions not poured into graduated apparatus like durette, measuring flask etc.?
Hot solutions may expand glass and thereby introduce errors in volume measurement.
- Why do we heat the oxalic acid to 60o– 70o C?
Heating is done to enhance the rate of reaction and increase activation energy.
- What happens if we heat oxalic acid above 100o C?
It may decompose oxalic acid into carbon dioxide [CO2] and carbon monoxide [CO].
- What is autocatalysis?
The reaction in which product acts as a catalyst to the reaction.
- Should a titration flask also be rinsed?
No, rinsing of the flask will increase the volume more than pipetted one.