In the reaction h2+n2 --> 2 nh3,
what coefficient should be placed in front of h2 to balance the reaction?
1.
2.
3.
no coefficient is needed.

Explanation:

A balanced equation is defined as the equation which contains same number of atoms on both reactant and product side.

For example,

Number of atoms on reactant side are as follows.

Number of atoms on product side are as follows.

Therefore, balance this equation by multiplying by 3 on reactant side.

Hence, the balanced equation is as follows.

Thus, we can conclude that a coefficient 3 should be placed in front of to balance the reaction.

catya your not at all which answer i've seen you do this on another question!