#### Answer

2(NH4NO3) -> 2N2 + O2 + 4(H2O)

#### Work Step by Step

NH4NO3 -> N2 + O2 + H2O
First balance the Ns - There are 2 on the left and 2 on the right so we are done.
Next we choose the Hydrogens since they only appear once on each side. We have 4 on the left and 2 on the right so we multiply H2O by 2
NH4NO3 -> N2 + O2 + 2(H2O)
Now we can do the Os. We have 3 on the left and 4 on the right.
We start by multiplying the left side by 2 to give us an even number (6)
2(NH4NO3) -> N2 + O2 + 2(H2O)
Now we rebalance the Ns - there are 4 on the left and 2 on the right so we multiply N2 by 2
2(NH4NO3) -> 2(N2) + O2 + 2(H2O)
Next we do the Oxygens. We have 6 on the left and only 4 on the right so we need to add 2 more. We can do this by doubling the O2
2(NH4NO3) -> 2N2 + 2(O2) + 2(H2O)
Now we have to balance the Hs. We have 8 on the left and only 4 on the right so we need to double the 2(H2O) to 4(H2O)
2(NH4NO3) -> 2N2 + 2(O2) + 4(H2O)
Now we have too many Os on the right side - 8 but only 6 on the left so we need to remove 2. We can do this by removing one of the O2s to give
2(NH4NO3) -> 2N2 + O2 + 4(H2O)