As our journey progresses, now we will explore Science Chapter- 2 Acid, Bases, and Salts. This chapter is about acids and bases and how they cancel out each other’s effects. This chapter consists of 7 marks and 8.75% in the exam. How do acids and bases react with each other? What is the reaction between metal carbonates and acids etc? Science is much more visible in everyday life. It finds its use in different places. Above all, scoring full marks in any subject is a matter of systematic study, and science is no different. Apart from knowing the important topics and learning them thoroughly, they must also be understood practically.
Key Topics of the Chapter
- Understanding the chemical properties of acids and bases
- Acids and bases in the laboratory
- How do acids and bases react with metals
- What are olfactory indicators?
- How do metal carbonates and metal hydrogen carbonates react with Acids?
- How do acids and bases react with each other?
- Reaction of metallic oxides with acids
- Reaction of nonmetallic oxide with base
- What do all acids and bases have in common?
- What happens to an acid dissolved in water
- When a base is dissolved in a water solution
- How strong are acid and base solutions
- Importance of pH in everyday life
- More about salts
- pH of salts
- Chemicals from common salt
- Are the crystals of salt really dry
- Questions based on the chapter
Importance of Learning Chapter 2
This chapter is based on Acid, base, and salt forms and one of the most important fundamentals of science. Class 10th Science Chapter 2 is very important as its concepts are used in higher classes too. Also in competitive exams like IIT JEE, NEET, etc. This chapter gives the fundamental knowledge of how acids and bases react in the environment. It tells about how hydrogen ions and hydroxide ions move in a reaction and form salts. Different chemical reactions can be asked from this chapter. Learn the concepts that are behind them instead of mugging them up.
Key Facts about Acid, Bases and Salts
- Acid-base indicators are dyes or mixtures of dyes that are used to indicate the presence of acids and bases.
- The acidic nature of a substance is due to the formation of H+ (aq) ions in solution. The formation of OH– (aq) ions in solution is responsible for the basic nature of a substance.
- When an acid reacts with a metal, hydrogen gas is evolved and a corresponding salt is formed.
- When a base reacts with a metal, along with the evolution of hydrogen gas a salt is formed which has a negative ion composed of the metal and oxygen.
- When an acid reacts with a metal carbonate or metal hydrogen carbonate, it gives the corresponding salt, carbon dioxide gas, and water.
- Acidic and basic solutions in water conduct electricity because they produce hydrogen and hydroxide ions respectively.
- The strength of an acid or an alkali can be tested by using a scale called the pH scale (0-14) which gives the measure of hydrogen ion concentration in a solution.
- A neutral solution has a pH of exactly 7, while an acidic solution has a pH of less than 7, and a basic solution has a pH of more than 7.
- Living beings carry out their metabolic activities within an optimal pH range.
- Mixing concentrated acids or bases with water is a highly exothermic process.
- Acids and bases neutralize each other to form corresponding salts and water.
- The water of crystallization is the fixed number of water molecules present in one formula unit of salt.
- Salts have various uses in everyday life and industries.
How to Plan Your Preparation?
The chapter consists of 7 marks and 8.75%. It is an important chapter as its concepts will be further used in class 11. Students must focus on preparing it conceptually and remember the methods of working with acids and bases. Now we will discuss some tips on how to prepare:
- Read the chapter carefully.
- Mark the important areas.
- Make notes of the important topics.
- Begin with definitions and try to learn chemical reactions.
- Learn from examples.
- NCERT has multiple examples that can be used for comprehensive learning.
- Try to comprehend how and why the reaction occurs.
- Learn by writing the chemical equation.
- Write word equations then convert them into symbolic representations.
- Practice balancing the equation regularly. One question can come on this.
- Learn the differences between acids, bases, and salts.
- Learn how to differentiate between them based on their pH value.
- Solve exercises and questions at the end of the chapter.
- Practice from examples given in the chapter.
ToppersSky Resources for Learning?
With the ToppersSky app, you can easily purchase any chapter and access features designed to make your learning simpler and more effective.
- Chapter videos: Students must watch the videos on different chapters and learn in an easy format.
- Minku and Minki questions answers: With different questions being asked students will solve the questions easily and overcome their doubts.
- How to write an answer: Learn to write clearly and in a structured format.
- Important questions and answers: You can know the important questions that can be asked in the exams.
Some Exam-Based Tips
- Understand the type of question.
- Short answer type questions: They might include definitions and simple reactions.
- Numerical questions: Questions on calculating pH.
- Application-based questions: Real-life scenario questions, like the use of antacids and the effects of acid rain.
Some Questions For Practice:
1. Concept-Based Questions
- Define acids and bases with examples.
- List chemical properties of acids.
Eg: Acid Examples:
- Hydrochloric Acid (HCl) – Found in stomach acid, used in cleaning products.
- Acetic Acid (CH₃COOH) – Found in vinegar.
- Nitric Acid (HNO₃) – Used in fertilizers and explosives.
- Sulfuric Acid (H₂SO₄) – Used in car batteries, and industrial processes.
- Citric Acid (C₆H₈O₇) – Found in citrus fruits like lemons and oranges.
Base Examples:
- Sodium Hydroxide (NaOH) – Found in lye and used in soap making.
- Calcium Hydroxide (Ca(OH)₂) – Also called slaked lime, used in water treatment.
- Ammonia (NH₃) – Used in cleaning products and fertilizers.
- Magnesium Hydroxide (Mg(OH)₂) – Found in milk of magnesia, used as an antacid.
- Potassium Hydroxide (KOH) – Used in making biodiesel and soaps.
2. Numerical Questions
Q1. What is the approximate pH of lemon juice, and is it acidic or basic?
Ans. Lemon juice has a pH of around 2-3, making it acidic.
Q2. If the concentration of hydrogen ions (H⁺) in a solution is 1 × 10⁻⁴ M, what is the pH of the solution?
Ans The pH is calculated using the formula:
pH=−log[H+]
Substitute the given concentration:
pH=−log(1 × 10⁻⁴ )=4
3. Reaction Based Questions
- Write a balanced chemical equation for the reaction of hydrochloric acid with sodium hydroxide.
HCl (aq)+NaOH (aq)→NaCl (aq)+H2O (l)
4. Application Based Questions
- Why do farmers add slaked lime to the soil?
Farmers add slaked lime (calcium hydroxide) to the soil to reduce its acidity. It neutralizes excess acid, improves soil pH, and enhances nutrient availability for plants.
- What is the use of baking soda in fire extinguishers?
Baking soda (sodium bicarbonate) releases carbon dioxide when heated, smothering flames by cutting off oxygen, which helps extinguish fires.
Effective Tips for Preparation
- Make notes: It is highly recommended that you make notes as you progress with your chapters. Use different color markers to define critical topics while making notes. They must contain essential chemical reactions and diagrams. Notes always help you with a quick brief revision. You do not always have to refer to the book to learn. Make handy notes that have abbreviations of important topics that can help you memorize easily.
- Solve sample question papers: Board exams not only test your knowledge but also your temper. Make sure that you have practiced solving exam sample question papers. They help you to give a real-time experience of the board exam environment. By the marks you have obtained, you can analyze your preparation.
- Revise: It is very important to revise what you have learned. Without revision, there is a chance that you might forget it. Give time for regular revision and practice. Revise regularly so that you don’t have to revise the entire course at once. Break your syllabus into small parts and revise.
Conclusion
Science is a subject that requires learning, understanding, and revision. It is a subject that needs regular practice. Students can use different resources to learn about it. The use of animated videos on ToppersSky is going to be very beneficial for the students as it makes learning easy and they can remember it for a long time.
Frequently Asked Questions
1. What happens when an acid reacts with metal?
When an acid reacts with metal, hydrogen gas is evolved and salt is formed.
2. What happens when the base reacts with metal?
When a base reacts with metal, hydrogen gas is formed along with a salt that has a negative ion of metal and oxygen.
3. Why do acidic and basic solutions in water conduct electricity?
They conduct electricity because they produce hydrogen and hydroxide ions respectively.
4. What is the total number of marks for the chapter?
The chapter consists of a total of 7 marks, which makes it 8.75%.
Also Read: How to Get 90+ Marks in Science Class 10th NCERT Exam
