Some Basic Concepts Of Chemistry Question 27
Question: Silver oxide $ (Ag _2O) $ decomposes at temperature $ 300{}^\circ C $ yielding metallic silver and oxygen gas. A 1.60 g sample of impure silver oxide yields 0.104 g of oxygen gas. What is the per cent by mass of the silver oxide in the sample?
Options:
A) 5.9
B) 47.125
C) 94.25
D) 88.2
Show Answer
Answer:
Correct Answer: C
Solution:
[c] Let mass of $ Ag _2O=xg $
$ \begin{matrix} Ag _2O & \xrightarrow{{}} & 2Ag & +\frac{1}{2}O _2 \\ \overset{xg}{\mathop{232g}}, & {} & {} & \frac{1}{2}\times 32=16g,O _2 \\ \end{matrix} $
$ \frac{16}{232}\times x=0.104\Rightarrow x=1.508g $ % of $ Ag _2O=\frac{1.508}{1.6}\times 100=94.25 $ %
