Question

A sample of soil is mixed with water and allowed to settle. The clear supernatant solution turns the pH paper yellowish-orange. Which of the following would change the colour of this pH paper to greenish-blue? 

(a) Lemon juice 

(b) Vinegar 

(c) Common salt 

(d) An antacid

Answer 1

The answer is (d) An antacid

• Sample solution turn pH paper yellowish-orange which confirms the acidic nature of the sample. 
• In order to make the color to greenish-blue we have to add an antacid