Carbon and oxygen form two known compounds. One compound contains $42.9\%$ carbon,while the other contains $27.3\%$ carbon. This illustrates the law of:

$1.0 \ g$ of an oxide of $A$ contained $0.5 \ g$ of $A$. $4.0 \ g$ of another oxide of $A$ contained $1.6 \ g$ of $A$. The data indicate the law of:

The law of multiple proportions was proposed by

Which one of the following pairs of compounds illustrates the law of multiple proportions?

$5.06 \ g$ of pure cupric oxide $(CuO)$ on complete reduction gives $4.04 \ g$ of metallic copper. In another experiment,$1.3 \ g$ of metallic copper is dissolved in nitric acid and the resulting solution is carefully dried to yield $1.63 \ g$ of $CuO$. Which law of chemical combination is illustrated by these results?

Which of the following pairs of compounds does not demonstrate the law of multiple proportions?