The ammonia evolved from $2 \ g$ of a compound in Kjeldahl's estimation of nitrogen neutralises $10 \ mL$ of $2 \ M \ H_2SO_4$ solution. The weight percentage of nitrogen in the compound is

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

The functional groups that are responsible for the ion-exchange property of cation and anion exchange resins,respectively,are :

Identify the incorrect statements regarding primary standard of titrimetric analysis.
$(A)$ It should be purely available in dry form.
$(B)$ It should not undergo chemical change in air.
$(C)$ It should be hygroscopic and should react with another chemical instantaneously and stoichiometrically.
$(D)$ It should be readily soluble in water.
$(E)$ $KMnO_4$ and $NaOH$ can be used as primary standard.
Choose the correct answer from the options given below:

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?

Estimation of $CO$ is done by using: