In Carius method of estimation of halogen,$0.45 \ g$ of an organic compound gave $0.36 \ g$ of $AgBr$. Find out the percentage of bromine in the compound. (Molar masses : $AgBr = 188 \ g \ mol^{-1}$,$Br = 80 \ g \ mol^{-1}$) (in $\%$)

During the estimation of $C$ and $H$,the $H_2O$ produced is absorbed in which of the following?

$x \ mg$ of an organic compound was analysed by the Kjeldahl method. The ammonia evolved was absorbed in $50 \ mL$ of $0.5 \ M \ H_2SO_4$. The unused acid required $60 \ mL$ of $0.5 \ M \ NaOH$ solution for complete neutralization. If the percentage of nitrogen in the compound is $56$,the value of $x$ is:

$0.53 \ g$ of an organic compound $(x)$ when heated with excess of nitric acid (concentrated) and then with silver nitrate gave $0.75 \ g$ of silver bromide precipitate. $1.0 \ g$ of $(x)$ gave $1.32 \ g$ of $CO_2$ gas on combustion. The percentage of hydrogen in the compound $(x)$ is . . . . . . $\%$. [Nearest Integer]
[Given : Molar mass in $g \ mol^{-1} H : 1, C : 12, Br : 80, Ag : 108, O : 16$; Compound $(x) : C_xH_yBr_z$] (in $\%$)

The number of moles of $CuO$ that will be utilized in the Dumas method for the estimation of nitrogen in a sample of $57.5 \ g$ of $N,N$-dimethylaminopentane is $..... \times 10^{-2}$. (Nearest integer)

Fill in the blanks:
$(1)$ ........... solution is added to produce the precipitate of $BaSO_4$ in the estimation of sulphur.
$(2)$ .......... and .... precipitate will be produced by the estimation of phosphorus.
$(3)$ How many elements are estimated in organic compounds?
$(4)$ ......... gas is produced in the Dumas method,but ....... gas is produced in the Kjeldahl's method.