Which one of the following can be used as an acid-base indicator by a visually impaired student?Deselect Answer Vanilla essence Turmeric Methyl orange Litmus

To determine which one of the following can be used as an acid-base indicator by a visually impaired student, we need to consider the properties of each option.

1. Vanilla essence: Vanilla essence is not typically used as an acid-base indicator. It is commonly used as a flavoring agent in cooking and baking, but it does not change color in the presence of acids or bases.

2. Turmeric: Turmeric is a natural dye that can be used as an acid-base indicator. It turns reddish-brown in the presence of bases and yellow in the presence of acids. This color change can be easily detected by a visually impaired student.

3. Methyl orange: Methyl orange is a synthetic dye commonly used as an acid-base indicator. It changes color from red in acidic solutions to yellow in basic solutions. However, since it is a synthetic dye, it may not be easily accessible or suitable for visually impaired students.

4. Litmus: Litmus is a natural dye extracted from lichens and is widely used as an acid-base indicator. It turns red in acidic solutions and blue in basic solutions. However, the color change may not be easily distinguishable for visually impaired students.

Based on these considerations, the best option for a visually impaired student to use as an acid-base indicator would be turmeric. Its distinct color change from yellow to reddish-brown can be easily detected and interpreted.