Given the mass of aluminum sulfide
= 21.0 g
Molar mass of
= 
Calculating the moles of
:

Each mole
has 3 mol S.
Each mole S constitutes 
Calculating atoms of S in 0.14 mol
:

= 
Answer:
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Explanation:
Answer:

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Answer:
1. NaN₃(s) → Na(s) + 1.5 N₂(g)
2. 79.3g
Explanation:
<em>1. Write a balanced chemical equation, including physical state symbols, for the decomposition of solid sodium azide (NaN₃) into solid sodium and gaseous dinitrogen.</em>
NaN₃(s) → Na(s) + 1.5 N₂(g)
<em>2. Suppose 43.0L of dinitrogen gas are produced by this reaction, at a temperature of 13.0°C and pressure of exactly 1atm. Calculate the mass of sodium azide that must have reacted. Round your answer to 3 significant digits.</em>
First, we have to calculate the moles of N₂ from the ideal gas equation.

The moles of NaN₃ are:

The molar mass of NaN₃ is 65.01 g/mol. The mass of NaN₃ is:

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