If 3.907 g carbon combines completely with 0.874 g of hydrogen to form a compound, what is the percent composition of this compound?
And, of course for a binary compound,
The compound contains
The mass of the compound must be the sum of the masses of
The formula for percent by mass is
#color(blue)(bar(ul(|color(white)(a/a)"% by mass" = "mass of element"/"mass of compound" × 100 %color(white)(a/a)|)))" "#
NOTE: You could have gotten the
That method is simpler, but I prefer using the first method.
If you make a mistake in calculating
The first method does not depend on the