Answer: The coefficient for the diatomic oxygen (O2) is 3.
Explanation:
To know the coefficient for the diatomic Oxygen, we need to balance the equation.
Fe + O2 -------> Fe2O3
LHS of the equation; Fe = 1 , O2 = 1
RHS of the equation; Fe = 2 , O = 3
∴ Multiply 'Fe' on the LHS of the equation by 4 and O2 by 3
Doing that will give the balance equation which is;
4 Fe + 3 O2 --------> 2 Fe2O3
The coefficient for the diatomic oxygen (O2) as seen from the equation is 3.
Because that solid is frozen liquid, so when it gets heated up, it will melt. Like Ice.
Hope I Helped! :)