Question

Ammonium perchlorate (NH,C102) is the solid rocket fuel used by the U.S. Space Shuttle. It reacts with itself to produce nitrogen gas (N), chlorine gas (C12), oxygen gas (O2), water (H20), and a great deal of energy. What mass of water is produced by the reaction of 5.23 g of ammonium perchlorate? Be sure your answer has the correct number of significant digits. x 3 ?

Answer 1

2NH4ClO4 ---> N2 +2 O2 +Cl2 + 4H2O

this is the balanced reaction of decomposition of ammonium perchlorate

2 mole perchlorate yields 4 mols water ,therefore mol ratio = 1:2

we need molar mass of perchlorate

=[1*14.01 + 4*1.01 + 1*35.45 + 4*16]g/mol = 117.49 g/mol

mols of NH4ClO4 present = mass of NH4CLO4/molar mass
= 5.23 g/117.49 g/mol =0.0445144 mols

use mole ratio to get mols of water formed
mols of water formed = [2]*0.0445144 mols=0.0890288 mols
molar mass of water =18.01528 g/mol
mass of water formed = 18.01528 g/mol*0.0890288 mols= 1.6039 g
round it to 3 significant figures

mass of water produced = 1.60 g
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