Question

Silver nitrate solution is kept in brown bottles in the laboratory because:
(A) it reacts with ordinary bottles
(B) ordinary bottles catalyse the decomposition
(C) the materials of brown bottles do not react with it
(D) brown bottles cut the passage of light through it

Answer 1

Hint: Think about the benefits of dark brown bottles. Nowadays, we wear goggles or shades when we go out in daylight. Think about the benefits of wearing those dark shades and then attempt this question.

Complete step by step answer:
- Let’s look at the question. We are aware that ordinary lab reagent bottles are unreactive. They do not catalyse any kind of reactions and that’s why they are used to store almost all kind of compounds except peroxides.
- Silver nitrate is a highly reactive compound. When exposed to light, it undergoes hydrolysis to give silver oxide which is brownish black in colour and nitric acid. This implies silver nitrate is sensitive to light.
- Brown bottles inhibit the passage of light through it. They do not allow light rays to pass through it.
- If silver nitrate is stored in transparent glass bottles, it reacts with light radiations and hydrolysis takes place.
- But if silver nitrate is stored in dark conditions which is possible with the help of dark brown bottles, also known as amber coloured bottles.
-Therefore, silver nitrate solution is kept in brown bottles in the laboratory because (D) brown bottles cut the passage of light through it.
So, the correct answer is “Option D”.

Note: Remember brown coloured glass prevents passage of light through it. Ordinary glass is transparent to normal light radiations. That is why, we wear shades while venturing out in the sun in order to protect our eyes from harmful UV radiations.