Question

1. What is the sum of the coefficients when the following equation is balanced using the lowest, whole numbered coefficients?

NH3(g) + O2(g) => NO (g) + H2O(g)
Group of answer choices
a, 19
b, 17
c, 15
d, 13
e, 21

Answer 1

A: 19

Step-by-step explanation:

It takes trial and error to balance a chemical equation, but after fidgeting with it for a while the lowest, whole-number coefficients are as follows:

4NH3(g)+5O2(g)⇒4NO(g)+6H2O(g)

We can check this by simply counting the number of molecules on either side of the equation, and adjusting as needed. It's important to remember that we can only ever change the coefficients to balance, never the subscripts.

Once counting the coefficients, we reach a sum of 19.

4+5+4+6=19