Step 1
The reaction provided:
2 NaN3 (s) ⇨ 2 Na (s) + 3 N2 (g) (completed and balanced)
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Step 2
Information provided:
100.0 g NaN3 decomposes
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Information needed:
The molar masses of:
NaN3) 65.00 g/mol
N2) 28.00
(please, the periodic table is useful here)
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Step 3
Procedure
By stoichiometry,
2 NaN3 (s) ⇨ 2 Na (s) + 3 N2 (g)
2 x 65.00 g NaN3 ----------------- 3 x 28.00 g N2
100.0 g NaN3 ----------------- X
X = 100.0 g NaN3 x 3 x 28.00 g N2/2 x 65.00 g NaN3
X = 64.62 g
Answer: 64.62 g of N2 produced