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nitrogen and hydrogen react to form ammonia. The unbalanced equation is

N2 + H2 > NH3

How many ammonia molecules are formed by the reaction of three nitrogen molecules?

Thank You!

Donaldson Tan:
this is simple balancing. if you are not sure using integer coefficient, why not try fractions?

N2 + H2 -> NH3

2N on LHS and 1 N on RHS, so coefficient of N2 = 1/2

2H on LHS and 3H on RHS, so coefficient of H2 = 3/2

1/2 N2 + 3/2 H2 -> NH3

multiply through out by lowest common multiple of the denominators to convert the fractions to integer.

Solution: N2 + 3H2 -> 2NH3 (multiply by 2 through out)

 N2 + H2 -> NH3
This is not a balanced equation because on reactants side there are two H atoms and two N atoms whereas on product side there are 3 H atoms and 1 N it is not balanced ,the balanced equation will be :
 N2 + 3H2 > 2NH3
now on product side there are 2 N atoms and 6 H atoms ( 2*3). and on reactant side also there are 2 N atoms and 6 H atoms (3*2). So this equation is balanced.

Now to react with if you have 3 N2 molecules then the equation will be:
 3N2 + 9H2 > 6NH3
Therefore 3 nitrogen molecules will for 6 ammonia molecules.


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