# Calculating Calories of Heat Produced

a) If 5.0 moles of H2 react, how many calories of heat are produced? (Using the bal equation: N2 + 3H2 -> 2NH3 + 21941 calories)

b) How many grams of H2 are needed to produce 55.0 grams of NH3?

c) Is this reaction endothermic or exothermic?

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#### Solution Preview

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a) From the equation we see that if 3 moles of H2 fully react, then we get 21941 calories.

So if 5 moles of H2 fully react, we get:

Q=5/3 * 21941 = 36568 Cal.

b) Again if we look at the species coefficients in the equation we see that if 3 moles of H2 fully react, we get 2 moles of ...

#### Solution Summary

The solution provides a detailed, step-by-step walk through of the calculations one must do to find the number of calories of heat produced from a hydrogen reaction, using the bai equation, as well as determining if the reaction is endo- or exothermic.