Acid and Alkalis

Free sample questions

Acid and Alkalis — sample Science questions with answers

1. Question 1

   Which of the following is a property of acids?

   • ABitter taste and slippery
   • BSour taste and corrosive
   • CSweet taste and does not react with metals
   • DTasteless and neutral

   Answer: B. Sour taste and corrosive

   Acids usually have a sour taste and are corrosive. Bitter taste and slippery are properties of alkalis.

2. Question 2

   A solution with pH 3 is more _________ than a solution with pH 5.

   • Aalkaline
   • Bacidic
   • Cneutral
   • Dpure

   Answer: B. acidic

   A lower pH value indicates higher acidity. pH 3 is more acidic than pH 5.

3. Question 3

   What is the colour of blue litmus paper when dipped into an acid?

   • ABlue
   • BRed
   • CGreen
   • DPurple

   Answer: B. Red

   Blue litmus paper turns red in acid. Red litmus remains red in acid.

4. Question 4

   Vinegar contains __________ acid.

   • Asulphuric
   • Bnitric
   • Cethanoic (acetic)
   • Dhydrochloric

   Answer: C. ethanoic (acetic)

   Vinegar contains ethanoic (acetic) acid. Sulphuric and nitric acids are strong acids not found in vinegar.

5. Question 5

   What substance is used to measure the pH of a solution more accurately?

   • ALitmus paper
   • BUniversal pH paper
   • CDistilled water
   • DSalt

   Answer: B. Universal pH paper

   Universal pH paper gives a more accurate pH value compared to litmus paper which only indicates whether it is acid or alkali.