Answer:
![2H_2+O_2=2H_2O](https://img.qammunity.org/2021/formulas/chemistry/middle-school/8fw3744l40xa9xv6tyceb16h1d8r4f7rvl.png)
Step-by-step explanation:
The chemical formula for hydrogen is H while chemical formula for oxygen is O
Considering that two moles of hydrogen and 2 moles of oxygen react to form water, the equation will be
![2H_2+2O_2=H_2O](https://img.qammunity.org/2021/formulas/chemistry/middle-school/ambiamueccsqx4hdn4ay0qretc3huji22k.png)
The number of oxygen molecules don't balance on both LHS and RHS hence to balance it, we put it as follows
![2H_2+O_2=2H_2O](https://img.qammunity.org/2021/formulas/chemistry/middle-school/8fw3744l40xa9xv6tyceb16h1d8r4f7rvl.png)
Normally, two moles of hydrogen require only one mole of oxygen to form two moles of water.