General Chemistry

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Calculation: Determining Partial Pressures of Ideal Gases


Sodium azide, $Na{N}_{3}$, is commonly used as the gas-forming propellant in airbag designs. Another azide compound, hydrazoic acid ($H{N}_{3}$), is a colorless and explosive liquid that decomposes on heating based on the following balanced reaction:

$$2 H{N}_{3}\ (g)\xrightarrow [ ]{ } {H}_{2}\ (g) + 3{N}_{2}\ (g)$$

Complete the following statement regarding partial pressures of hydrogen and nitrogen. Assume temperature and volume of the reaction vessel are kept constant, and that gases behave as ideal gases.

If 7 atm of $H{N}_{3}$ initially decomposes, the partial pressure of hydrogen is

atm and the partial pressure of nitrogen is

atm when the reaction is complete.