According to Dalton's atomic theory,atoms of an element are

Atoms combine in chemical reactions to form:

Which law is illustrated by compounds $H_2O$ and $H_2O_2$ formed from two different elements,$H$ and $O$?

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

Zinc sulfate crystals contain $22.65\%$ of zinc and $43.9\%$ of water. If it follows the law of definite proportions,how many grams of $Zn$ are required to obtain $20 \, g$ of crystals?

Define the law of multiple proportions. Explain it with two examples. How does this law point to the existence of atoms?