Estimation of $CO$ is done by using:

$30 \ mL$ of acid solution is neutralized by $15 \ mL$ of a $0.2 \ N$ base. The strength of acid solution is $.............. \ N$.

$K_2Cr_2O_7$ is preferred to $Na_2Cr_2O_7$ for use in volumetric analysis as a primary standard because

During the preparation of Mohr's salt solution (Ferrous ammonium sulphate),which of the following acid is added to prevent hydrolysis of $Fe^{2+}$ ion?

Why is it necessary to wash the precipitate before measuring it quantitatively?

The ammonia evolved from the treatment of $0.30 \, g$ of an organic compound for the estimation of nitrogen was passed in $100 \, mL$ of $0.1 \, M$ sulphuric acid. The excess of acid required $20 \, mL$ of $0.5 \, M$ sodium hydroxide solution for complete neutralization. The organic compound is: