In an estimation of bromine by Carius method,$1.6 \ g$ of an organic compound gave $1.88 \ g$ of $AgBr$. The mass percentage of bromine in the compound is..........
(Atomic mass,$Ag = 108, Br = 80 \ g \ mol^{-1}$)

In the Carius method for the estimation of halogens,$0.15 \, g$ of an organic compound gave $0.12 \, g$ of $AgBr$. Find the percentage of bromine in the compound. (in $\%$)

$A$ sample of $0.50 \, g$ of an organic compound was treated according to Kjeldahl's method. The ammonia evolved was absorbed in $50 \, mL$ of $0.5 \, M \, H_{2}SO_{4}$. The residual acid required $60 \, mL$ of $0.5 \, M \, NaOH$ solution for neutralisation. Find the percentage composition of nitrogen in the compound. (in $\%$)

What is the reason for passing dry air through the combustion tube during the estimation of $C$ and $H$?

In the Kjeldahl method,$0.35 \ g$ of an organic compound produces ammonia,which is absorbed in $100 \ mL$ of $0.1 \ M \ H_2SO_4$. The excess $H_2SO_4$ requires $154 \ mL$ of $0.1 \ M \ NaOH$ for titration. Calculate the percentage of nitrogen in the compound. (Given atomic masses: $C=12, H=1, O=16, N=14, S=32$)

In Dumas's method for estimation of nitrogen,$0.25 \, g$ of an organic compound gave $40 \, mL$ of nitrogen collected at $300 \, K$ temperature and $725 \, mm$ pressure. If the aqueous tension at $300 \, K$ is $25 \, mm,$ the percentage of nitrogen in the compound is