Answer:
N, B, Be, C
Explanation:
N (Nitrogen) has 14.0067 B (Boron) has 10.81 Be (Beryllium) has 9 and C (Carbon) has 12
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:
Products have a lower total Gibbs free energy in comparison with the reagents total Gibbs free energy.
Explanation:
Hello,
Exergonic chemical reactions are those that the overall Gibbs free energy is negative, it means that the products have a lower total Gibbs free energy, turning out into a spontaneous chemical reaction. Such reactions are thermodynamically possible under standard conditions and they usually release heat.
Best regards.