Gay-Lussac's law of gaseous volumes is derived from $.......$.

$A$ pure sample of water contains $88.89\%$ of oxygen by mass and $11.11\%$ of hydrogen by mass. This is an example of which law?

$A$ box contains some identical red-coloured balls,labelled as $A$,each weighing $2 \ g$. Another box contains identical blue-coloured balls,labelled as $B$,each weighing $5 \ g$. Consider the combinations $AB, AB_2, A_2B$ and $A_2B_3$ and show that the law of multiple proportions is applicable.

"$A$ given compound always contains the same proportion of elements" is a statement of $-$

Two elements $x$ and $y$ have atomic masses $14$ and $16$ respectively. They form a series of five compounds $A, B, C, D, E$ in which the ratio of $x$ to $y$ is $1:2:3:4:5$. If compound $A$ contains $28$ parts by weight of $x$ and $16$ parts by weight of $y$,then in compound $C$,how many parts by weight of $x$ will combine with $24$ parts by weight of $y$?

Irrespective of the source,a pure sample of water always yields $88.89\%$ mass of oxygen and $11.11\%$ mass of hydrogen. This is explained by the law of