Question

A visually challenged student, has to perform a lab test to detect the presence of acid in a given solution. The acid-base indicator preferred by him will be

• A. blue litmus
• B. clove oil
• C. red cabbage extract
• D. Hibiscus extract

Answer 1

The correct option is B

clove oil

The correct option is B

The explanation for the correct option:

1. A visually challenged student will use an olfactory indicator to determine whether the solution is acidic or basic.
2. Some compounds change in smell when placed in acidic or basic solutions. They are referred to as olfactory indicators.
3. The olfactory indicators emit a characteristic odor.
4. We can determine whether a given sample solution is acidic or basic by analyzing the scent in olfactory indicators, which changes in an acidic or basic solution.
5. Examples include vanilla essence, onion, and clove oil.
6. Clove oil persists its smell in acidic solution while its smell is gone is a basic solution.

The explanation for the incorrect options:

Option (A): Blue litmus

1. Litmus is a natural indicator that is obtained from the extract of lichens.
2. It turns red in an acidic medium and blue in a basic medium.
3. Hence, it is an incorrect option.

Option (C): Red cabbage extract

1. Red cabbage is a natural indicator.
2. A substance known as anthocyanin can be found in red cabbage. In neutral substances, it changes its color to blue.
3. Hence, it is an incorrect option.

Option (D): Hibiscus extract

1. It is a natural indicator obtained from hibiscus extract.
2. Its color changes from dark pink to pale pink in acidic medium and dark gray to green in basic medium.
3. Hence, it is an incorrect option

Final answer: The acid-base indicator preferred by the visually challenged student will be clove oil.