17. Which one of the following can be used as an acid–base indicator by a visually impared student?
A. Litmus
B. Turmeric
C. Vanilla essence
D. Petunia leaves
Answer:C
17. Which one of the following can be used as an acid–base indicator by a visually impared student?
A. Litmus B. Turmeric C. Vanilla essence D. Petunia leaves