Acetamide has the molecular formula CH3CONH2. Which element makes up the greatest percentage by mass of acetamide?
Carbon has the greatest percent by mass at
To find the mass, add all the elements' masses together. Let's make a list to find the mass by element.
Carbon (2 of them) - weighs 12.011g ; 2 of them, so multiply by 2:
Hydrogen (5 of them) - weighs 1.008 ; 5 of them, so multiply by 5:
Oxygen (1 of them) - weighs 15.999g
Nitrogen (1 of them) - weighs 14.007g
Add these numbers together:
Now, make a ratio of the highest amt. element to the whole: