Question

In Gutzeit test, ______ reacts with mercuric chloride paper and produces _______ colour stain.

"

• A. Arsenious acid; yellow
• B. Arsine; orange
• C. Arsenious acid; orange
• D. Arsine; yellow

Hint:

Gutzeit test is used for arsenic impurity, and mercuric chloride paper develops a yellow stain.

Answer 1

The Correct Option is A

Concept:
The Gutzeit test is an important limit test used for the detection of arsenic impurity in pharmaceutical substances. It is based on the conversion of arsenic compounds into arsine gas, which reacts with mercuric chloride paper.

Step 1: Understanding the Gutzeit test.
In this test, arsenic present in the sample is converted into arsine gas. The arsine gas then comes in contact with mercuric chloride paper.

Step 2: Reaction with mercuric chloride paper.
The mercuric chloride paper develops a yellow stain due to the formation of arsenic-mercury complex.

Step 3: Relation with arsenious acid.
Arsenious acid is involved in the arsenic impurity test and produces the characteristic yellow stain in the Gutzeit method.

Step 4: Checking the options.
Option (A) correctly matches arsenious acid with yellow colour stain.
Option (B), (C), and (D) do not correctly match both the reacting substance and colour.

Step 5: Final answer.
Therefore, the correct answer is arsenious acid; yellow. \[ \boxed{\text{Arsenious acid; yellow}} \]