Day 2 class 7 Acids, Bases and Salts

Multiple Choice

Which of the following is a property of bases?

• A) Sour taste

• B) Bitter taste and slippery feel

• C) Turns blue litmus red

• D) Found in lemon juice

Multiple Choice

The sour taste in lemon is due to:

• A) Acetic acid

• B) Citric acid

• C) Lactic acid

• D) Hydrochloric acid

Open Ended

Explain why bitter gourd tastes different from tamarind.

Multiple Choice

Blue litmus paper dipped in lemon juice will turn:

• A) Red

• B) Blue

• C) Remain same

• D) Colorles

Match

Match acids and bases with their examples:

• Lemon

• Vinegar

• Soap

• Baking soda

Citric acid

Acetic acid

Base

Base

• Citric acid

• Acetic acid

• Base

• Base

Open Ended

Why do some people apply baking soda paste on areas stung by honeybees?

Multiple Choice

Which of the following is a mineral acid?

• A) Citric acid

• B) Acetic acid

• C) Hydrochloric acid

• D) Lactic acid

Multiple Choice

Which base is highly corrosive and used in drain cleaners?

• Ammonium hydroxide

• Sodium hydroxide

• Magnesium hydroxide

• Calcium hydroxide

Multiple Choice

Ammonium hydroxide is classified as a:

• A) Strong acid

• B) Weak acid

• C) Strong base

• D) Weak base

Multiple Choice

How do bases feel when touched?

• A) Rough

• B) Oily

• Slippery

• D) Powdery

Multiple Choice

Why should we never taste lab chemicals to test for acids/bases?

• A) They don’t taste nice

• B) They can be poisonous/corrosive

• C) Teachers don’t allow it

• D) They don’t show taste difference

Open Ended

List three differences between acids and bases in your own words.

Multiple Choice

Why does baking soda paste help in bee stings?

• It reduces pain by cooling

• It neutralises the acid in the sting

• It kills bacteria

• It dries the wound

Open Ended

Think of one more example where acids or bases are used to solve a real-life problem.

Multiple Choice

Which of these is NOT a base?

• A) Soap

• B) Baking soda

• C) Vinegar

• D) Ammonium hydroxide