(4) NH3+02- NO+H2O
balance the equation

4NH₃ + 5O₂ —> 4NO + 6H₂O

Explanation:

NH₃ + O₂ —> NO + H₂O

The above equation can be balance as follow:

NH₃ + O₂ —> NO + H₂O

There 3 atoms of H on the left side and 2 atoms on the right side. It can be balance by 4 in front of NH₃ and 6 in front of H₂O as shown below:

4NH₃ + O₂ —> NO + 6H₂O

There are 4 atoms of N on the left side and 1 atom on the right side. It can be balance by putting 4 in front of NO as shown below:

4NH₃ + O₂ —> 4NO + 6H₂O

There are 2 atoms of O on the left side and a total of 10 atoms on the right side. It can be balance by putting 5 in front of O₂ as shown below:

4NH₃ + 5O₂ —> 4NO + 6H₂O

Thus, the equation is balanced.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.