In the estimation of bromine,$0.5 \ g$ of an organic compound gave $0.40 \ g$ of silver bromide. The percentage of bromine in the given compound is $..... \ \%$ (nearest integer).
(Relative atomic masses of $Ag$ and $Br$ are $108 \ u$ and $80 \ u$,respectively).

Fill in the blanks:
$(1)$ .......... gas is produced in Kjeldahl's method and absorbed in ...........
$(2)$ The excess $H_2SO_4$ is added in Kjeldahl's method and then the remaining $H_2SO_4$ is titrated with a calculated ..........

Discuss the principle of estimation of halogens,sulphur and phosphorus present in an organic compound.

$A$ student has been given $0.314 \ g$ of an organic compound and asked to estimate Sulphur. During the experiment, the student has obtained $0.4813 \ g$ of barium sulphate. The percentage of sulphur present in the compound is . . . . . .
(Given Molar mass in $g \ mol^{-1}$: $S = 32$, $BaSO_4 = 233$) (in $\%$)

Discuss the Dumas method and its principles for the estimation of $N$ present in an organic compound.

In Dumas method for estimation of nitrogen, $0.50 \ g$ of an organic compound gave $70 \ mL$ of nitrogen collected at $300 \ K$ and $715 \ mm$ pressure. The percentage of nitrogen in the organic compound is . . . . . . $ \% $ (Aqueous tension at $300 \ K$ is $15 \ mm$).