Question

colourless sample was tested with the strip of pH paper. the the colour of the strip changed to green. The sample should be:
(a) tap water
(b) distilled water
(c) sodium hydroxide
(d) lemon juice



Pls answer. I think the answer is sodium hydroxide cuz it's a base. correct me if I'm wrong.​

Answer 1

Answer:

your answer is wrong because sodium hydroxide is basic in nature and of colour blue.

correct answer is distilled water

Answer 2

The correct answer is (b) Distilled Water.

Step-by-step explanation:

• The pH paper determines the hydrogen ion concentration of a solution that is being tested.
• The pH value ranges from 0 to 14.
• 0 indicates highly acidic solution.
• 14 indicates highly basic solution.
• 7 indicates a neutral pH
• The colour codes for the above pH as present in the pH paper are:

1. Acidic pH range is represented by shades of red colour.
2. Basic pH range is represented by shades of blue colour.
3. Neutral pH range is represented by shades of green colour.

• Distilled water has a neutral pH (pH-7), so it will turn the pH paper green.
• Tap water water has dissolved carbon dioxide in it which is mildly acidic, so it will turn the pH paper yellowish green.
• Sodium hydroxide is an alkali (pH-12) so will turn the pH paper blue.
• Lemon juice is also acidic (pH-3) so it will turn the pH paper red.