General Properties of Acids MCQs Quiz | Class 10

Test your understanding of Class X Science (Code 086), Unit I: Chemical Substances – Nature and Behaviour. This quiz covers the general properties of acids, including indicators and basic reaction behaviors. Answer the following questions to check your mastery of the topic, then submit to view your score and download the PDF solution.

Overview of Acids

In Class 10 Science, Unit I, acids are defined as substances that furnish hydrogen ions (H+) in aqueous solutions. They are a fundamental part of chemical substances and nature. Acids generally taste sour and change the color of blue litmus paper to red.

Key Physical Properties

  • Taste: Acids have a characteristic sour taste (e.g., lemon juice, vinegar).
  • Indicators: They turn blue litmus red. Methyl orange turns red in acidic solutions, while phenolphthalein remains colorless.
  • Conductivity: Acidic solutions conduct electricity because they dissociate into ions in water.
  • Corrosive Nature: Strong mineral acids like sulphuric acid can cause severe burns and corrode metals.

Chemical Properties and Reactions

Acids react with various substances to produce predictable products:

Reactant General Reaction Product
Metal Acid + Metal Salt + Hydrogen Gas
Metal Carbonate Acid + Metal Carbonate Salt + CO2 + Water
Base Acid + Base Salt + Water (Neutralization)
Metal Oxide Acid + Metal Oxide Salt + Water

Indicators Summary

Indicators are dyes that change color when put into an acid or a base. Common indicators include:

  • Litmus: Blue to Red in acid.
  • Phenolphthalein: Colorless in acid.
  • Methyl Orange: Red in acid.
  • Olfactory Indicators: Substances like onion and vanilla extract lose their smell in bases but retain it in acids.

Extra Practice Questions

  1. What happens to the pH of water when a few drops of concentrated acid are added to it?
  2. Why does dry HCl gas not change the color of dry litmus paper?
  3. Name the acid present in tamarind.
  4. Write the chemical equation for the reaction of zinc granules with dilute sulphuric acid.
  5. Why are pickles and curd not stored in copper vessels?