Given the unbalanced equation:
_NO3- + 4H+ + Pb → Pb2+ + NO2 + 2H20
What is the coefficient of NO2 when the equation is correctly balanced?
1. 1
2. 2
3. 3
4. 4

Option (2) 2

Explanation:

NO3- + 4H+ + Pb → Pb2+ + NO2 + 2H2O

The equation above can be balance as follow:

There are 3 atoms of the left side and a total of 4 atoms on the right side. It can be balance by putting 2 in front NO3- and 2 in front of NO2 as shown below:

2NO3- + 4H+ + Pb → Pb2+ + 2NO2 + 2H2O

Now the equation is balanced.

The coefficient of NO2 is 2

the answer is a and have a great day