Question

As we studied, we can find substances of various acidity and basicity in our surroundings. Collect the samples of the following acidic and basic substances. With the help of the Universal indicator, estimate the pH value of each of the substances.

1. Orange juice
2. Lemon juice
3. Cold drink
4. Toothpaste
5. Soap solution
6. Tap water
7. Table vinegar
8. Baking powder
9. Table salt solution
10. Lime water

Answer 1

Sr. No.	Substance	Approximate pH	Nature	Colour with Universal Indicator
(i)	Orange juice	3.5 - 4.0	Acidic	Orange/Yellow-orange
(ii)	Lemon juice	2.2 - 2.5	Strongly Acidic	Pinkish Red/Red
(iii)	Cold drink	3.0 - 4.0	Acidic	Yellowish Orange
(iv)	Toothpaste	8.0 - 9.0	Mildly Basic	Greenish Blue
(v)	Soap solution	9.0 - 10.0	Basic	Blue
(vi)	Tap water	6.5 - 7.5	Neutral/Near Neutral	Green
(vii)	Table vinegar	2.5 - 3.0	Acidic	Orange-red
(viii)	Baking powder	8.5 - 9.0	Mildly Basic	Greenish Blue
(ix)	Table salt solution	7.0	Neutral	Green
(x)	Lime water	11.0 - 12.0	Strongly Basic	Purple/Dark Violet