Grade 7 : Science (Curiosity) - 2. Acids, Bases, Neutral (Set 1)

Question 1

Which of the following pH values indicates a highly acidic solution?

Accepted Answer

C) pH 2

Answer

A) pH 7

Answer

B) pH 8.5

Answer

D) pH 12

Question 2

What color does blue litmus paper turn when dipped into a basic (alkaline) solution?

Accepted Answer

A) Blue

Answer

B) Red

Answer

C) Green

Answer

D) Yellow

Question 3

Which of the following substances is generally considered a base?

Accepted Answer

B) Baking soda solution

Answer

A) Vinegar

Answer

C) Lemon juice

Answer

D) Carbonated water

Question 4

What is the characteristic taste of most acidic substances?

Accepted Answer

D) Sour

Answer

A) Bitter

Answer

B) Salty

Answer

C) Sweet

Question 5

A solution has a pH of exactly 7. What type of solution is it?

Accepted Answer

C) Neutral

Answer

A) Acidic

Answer

B) Basic

Answer

D) Highly alkaline

Question 6

When an acid reacts with a base, the reaction is typically called:

Accepted Answer

A) Neutralization reaction

Answer

B) Oxidation reaction

Answer

C) Reduction reaction

Answer

D) Precipitation reaction

Question 7

Red litmus paper turns blue when dipped into which type of solution?

Accepted Answer

B) Basic (Alkaline)

Answer

A) Acidic

Answer

C) Neutral

Answer

D) Distilled water

Question 8

Which of the following is NOT a property of acids?

Accepted Answer

D) They feel slippery to the touch

Answer

A) They taste sour

Answer

B) They turn blue litmus red

Answer

C) They react with metals to produce hydrogen gas

Question 9

Which everyday substance is a good example of a strong acid?

Accepted Answer

A) Hydrochloric acid (present in stomach acid)

Answer

B) Hand soap

Answer

C) Milk

Answer

D) Pure water

Question 10

If a solution has a pH of 10, how would you classify it?

Accepted Answer

B) Basic (Alkaline)

Answer

A) Acidic

Answer

C) Neutral

Answer

D) Extremely corrosive acid