Answer:
<u><em>See attachment for explanations.</em></u>
Explanation:
It becomes a acceptor because in an ionic bonding the element who gives out is a donor while the atom which accept is a acceptor
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:

So you get about:


So, the percent composition of Hydrogen in NH4HCO3 is 6.3%
Hope this Helps! :D
Answer: when two elements combine, A and B, the ratio of the weight of B combining with A is always a whole number
Explanation: