Question

What is the percent composition of hydrogen in NH4HCO3?

Answer 1

To find the Percent Composition of an atom, you use this formula:
Mass of element in the compound you're studying on ( in this case it's 5 since there is 5 Hydrogens) over the mass of the compound (which is here 79), Multiplied by 100 since you want a percent. 
So we get: 
$\frac{5}{79} * 100$
So you get about: 
$0.063 * 100$
$6.3$

So, the percent composition of Hydrogen in NH4HCO3 is 6.3%

Hope this Helps! :D

Answer 2

i hope this helps hydrogen in a compound =5 h atoms are present 
therefore % of composition =5/79 *100 so it equals 6.3%