---
title: "NCERT Solutions Class 7 Science Exploring Substances: Acidic, Basic, and Neutral"
url: https://www.swavid.com/science/class/7/chapter/exploring-substances-acidic-basic-and-neutral/ncert-solutions
dateModified: 2026-10-07T16:06:22+00:00
---

# NCERT Solutions Class 7 Science Exploring Substances: Acidic, Basic, and Neutral

This chapter's questions cover the identification, properties, and neutralisation reactions of acidic, basic, and neutral substances using natural indicators.

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## Activity 2.1: Let us explore

### Question 1

*Activity*

Do you observe any change in the colour of the blue litmus pieces?

**Solution**

1. Add a drop of each test sample onto pieces of blue litmus paper placed on a clean and dry white tile.
2. Observe that acidic samples turn blue litmus paper red, while basic and neutral samples do not change its blue colour.

**Answer:** Acidic samples turn blue litmus paper red, whereas basic and neutral samples show no colour change.

### Question 2

*Activity*

Record your observations in Table 2.1.

**Solution**

1. Test each sample from the given list using both blue and red litmus papers.
2. Record the observed colour changes for each sample systematically in Table 2.1.

**Answer:** Observations of colour changes for all tested samples are recorded in Table 2.1.

### Question 3

*Activity*

Repeat the same activity with pieces of red litmus paper as shown in Fig. 2.2b and record your observations in Table 2.1.

**Solution**

1. Add a drop of each test sample onto pieces of red litmus paper placed on a clean and dry white tile.
2. Observe that basic samples turn red litmus paper blue, while acidic and neutral samples show no colour change.

**Answer:** Basic samples turn red litmus paper blue, whereas acidic and neutral samples show no colour change.

## Holistic Lens

### Question 1

*2 marks · Very short answer*

Do you find lichens on trees in your neighbourhood?

**Solution**

1. Lichens grow on rocks and trees in regions that have abundant rainfall and clean air.
2. They may or may not be found locally depending on the environmental conditions and air quality of the neighbourhood.

**Answer:** Lichens may be found on trees in regions with abundant rainfall and clean air, but their presence depends on local environmental conditions.

> Common mistake: Stating that lichens are found everywhere without considering air quality and rainfall requirements.

## Activity 2.2: Let us relate and explore

### Question 1

*3 marks · Short answer*

Find out and write the names of the most common acids present in the following substances— Lemon________, Curd________, Tamarind________, Vinegar________.

**Part (i)**

1. Refer to Fig. 2.4 showing common acids in edible substances.
2. Lemon contains citric acid.

Answer (i): Citric acid

**Part (ii)**

1. Refer to Fig. 2.4 showing common acids in edible substances.
2. Curd contains lactic acid.

Answer (ii): Lactic acid

**Part (iii)**

1. Refer to Fig. 2.4 showing common acids in edible substances.
2. Tamarind contains tartaric acid.

Answer (iii): Tartaric acid

**Part (iv)**

1. Refer to Fig. 2.4 showing common acids in edible substances.
2. Vinegar contains acetic acid.

Answer (iv): Acetic acid

**Answer:** Lemon: Citric acid, Curd: Lactic acid, Tamarind: Tartaric acid, Vinegar: Acetic acid

> Common mistake: Confusing tartaric acid of tamarind with citric acid of lemon.

### Question 2

*2 marks · Very short answer*

Rub the baking soda solution between your fingers. What do you observe?

**Solution**

1. Rubbing baking soda solution between the fingers shows its touch property.
2. It feels soapy or slippery, which is a general characteristic of basic substances.

**Answer:** It feels soapy or slippery to touch.

> Common mistake: Describing the taste instead of the touch property when asked about rubbing between fingers.

## Activity 2.4: Let us find out

### Question 1

*Activity*

Observe and record any colour changes to the extract in Table 2.3.

**Solution**

1. Add lemon juice to red rose extract in test tube A and observe the colour change to red.
2. Add soap solution to red rose extract in test tube B and observe the colour change to green.

**Answer:** Red rose extract turns red in lemon juice and green in soap solution.

### Question 2

*Activity*

Repeat the same with the other samples used in Activity 2.1 and record your observations in Table 2.3.

**Solution**

1. Take drops of other samples from Activity 2.1 such as amla juice, vinegar, baking soda solution, and lime water.
2. Add them separately to red rose extract and record the resulting colour changes in Table 2.3.

**Answer:** Acidic samples turn red rose extract red, and basic samples turn it green.

### Question 3

*3 marks · Short answer*

Are the samples that change the colour of the flower extract to a shade of red the same as those that changed the colour of blue litmus paper to red? (Group A, Table 2.2)

**Solution**

1. Samples in Group A (such as lemon juice, amla juice, tamarind water, and vinegar) turn blue litmus paper to red, showing they are acidic.
2. These same acidic substances change the colour of the red rose extract to a shade of red.
3. Therefore, the samples that turn the flower extract red are the same as those that turn blue litmus paper to red.

**Answer:** Yes, the samples that change the flower extract to red are the same as those that turn blue litmus paper to red.

> Common mistake: Confusing the colour changes of acidic and basic substances with indicators.

### Question 4

*3 marks · Short answer*

Are the samples that change the colour of the flower extract to a shade of green the same as those that changed the colour of red litmus paper to blue? (Group B, Table 2.2)

**Solution**

1. Samples in Group B (such as soap solution, baking soda solution, lime water, and washing powder solution) turn red litmus paper to blue, showing they are basic.
2. These same basic substances change the colour of the red rose extract to a shade of green.
3. Therefore, the samples that turn the flower extract green are the same as those that turn red litmus paper to blue.

**Answer:** Yes, the samples that change the flower extract to green are the same as those that turn red litmus paper to blue.

> Common mistake: Stating that bases turn red rose extract blue instead of green.

### Question 5

*3 marks · Short answer*

Are the samples that do not change the colour of the flower extract the same as those that did not change the colour of red and blue litmus papers? (Group C, Table 2.2)

**Solution**

1. Samples in Group C (such as tap water, sugar solution, and salt solution) do not change the colour of either red or blue litmus paper because they are neutral.
2. These same neutral substances do not change the colour of the red rose extract.
3. Therefore, the samples that do not change the colour of the flower extract are the same as those that do not affect red and blue litmus papers.

**Answer:** Yes, the samples that do not change the colour of the flower extract are the same as those that do not affect red and blue litmus papers.

> Common mistake: Assuming neutral substances cause a colour change in natural indicators.

### Question 6

*3 marks · Short answer*

Can you now fill in the nature of the substances in Table 2.3?

**Solution**

1. Identify the colour produced by each sample when added to the red rose extract.
2. Classify samples that give a red shade as acidic in nature.
3. Classify samples that give a green shade as basic in nature, thereby completing Table 2.3.

**Answer:** Acidic samples are marked as acidic, and basic samples are marked as basic based on the red rose extract test.

> Common mistake: Incorrectly assigning acidic or basic nature without checking the observed indicator colour.

## Fascinating Facts

### Question 1

*3 marks · Short answer*

Can gardeners alter the colour of hydrangea flowers by adjusting the acidic or basic nature of the soil?

**Solution**

1. Yes, gardeners can alter the colour of hydrangea flowers by adjusting the acidic or basic nature of the soil.
2. Hydrangea flowers change colour depending on the soil pH, where acidic soil produces blue-coloured flowers.
3. In contrast, basic soil produces pink or red-coloured flowers.

**Answer:** Yes, gardeners can alter the colour by adjusting the soil's acidic or basic nature, as acidic soil gives blue flowers and basic soil gives pink or red flowers.

> Common mistake: Thinking flower colour is independent of soil conditions.

## Activity 2.5: Let us prepare

### Question 1

*Activity*

Record your observations in Table 2.4.

**Solution**

1. Turmeric paper turns red when tested with basic substances like soap solution, baking soda solution, and lime water.
2. Turmeric paper shows no change in colour and remains yellow when tested with acidic substances (like lemon juice, vinegar) and neutral substances (like water, salt solution).

**Answer:** Turmeric paper turns red with basic solutions and remains yellow with acidic and neutral solutions.

> Common mistake: Assuming turmeric paper turns red with all substances.

### Question 2

*2 marks · Very short answer*

Do all samples change the colour of the turmeric paper?

**Solution**

1. No, all samples do not change the colour of the turmeric paper.
2. Turmeric paper changes its colour only when tested with basic substances, remaining unchanged with acidic and neutral substances.

**Answer:** No, only basic samples change the colour of the turmeric paper to red.

> Common mistake: Stating that all samples alter the indicator colour.

### Question 3

*3 marks · Short answer*

Group the samples which do not change the colour of the turmeric paper.

**Solution**

1. The samples which do not change the colour of the turmeric paper include both acidic substances (such as lemon juice, amla juice, tamarind water, and vinegar) and neutral substances (such as tap water, sugar solution, and salt solution).
2. Compared to Table 2.2, these comprise the samples belonging to Group A (acidic) and Group C (neutral).
3. This shows that turmeric paper can identify basic substances but cannot differentiate between acidic and neutral substances.

**Answer:** Acidic and neutral samples from Group A and Group C do not change the yellow colour of turmeric paper.

> Common mistake: Forgetting that neutral substances also fail to change turmeric paper colour.

## Activity 2.6: Let us investigate

### Question 1

*Activity*

Check the odour again.

**Solution**

1. Smell the onion strips after adding tamarind water or baking soda solution to observe any change in their characteristic smell.

**Answer:** Observe the odour of the strips after adding the substances.

### Question 2

*2 marks · Very short answer*

Do you notice any change in the odour of the onion strips before and after putting tamarind water and baking soda solution on them?

**Solution**

1. The characteristic smell of onions is retained when an acidic substance like tamarind water is added.
2. The characteristic smell of onions disappears or cannot be detected when a basic substance like baking soda solution is added.

**Answer:** Yes, the odour of onion strips changes in a basic medium (baking soda solution) while it remains unchanged in an acidic medium (tamarind water).

> Common mistake: Confusing the effect of acidic and basic substances on the odour of olfactory indicators.

### Question 3

*Activity*

Note your observations.

**Solution**

1. Record whether the characteristic odour of the onion strips is retained or destroyed upon treatment with acidic and basic substances.

**Answer:** Note down the observations regarding changes in odour.

### Question 4

*Activity*

Similarly, test the change in the odour with other acidic and basic substances and record your observations.

**Solution**

1. Test other substances such as vanilla extract or clove oil with various acids and bases to observe similar changes in odour.

**Answer:** Perform the test with other substances and record observations.

## Activity 2.7: Let us experiment

### Question 1

*2 marks · Very short answer*

Do you observe any colour change (Fig. 2.10a)?

**Solution**

1. When a drop of blue litmus solution is added to the diluted lemon juice solution, the colour of the solution turns red.
2. This indicates that lemon juice is acidic in nature, as acids turn blue litmus red.

**Answer:** The blue litmus solution turns red, showing that the lemon juice solution is acidic.

> Common mistake: Stating that blue litmus turns blue instead of red.

### Question 2

*2 marks · Very short answer*

What do you observe? Is there any change in the colour of the solution?

**Solution**

1. As drops of lime water are slowly added and swirled into the test tube, the acidic effect is gradually neutralised.
2. A stage comes when the colour of the solution changes from red back to blue.

**Answer:** The colour of the solution changes from red to blue as lime water is added.

> Common mistake: Failing to mention the transition from red to blue.

### Question 3

*3 marks · Short answer*

Can you predict why there is a change in colour?

**Solution**

1. Initially, the lemon juice solution is acidic and turns the blue litmus red.
2. Lime water is a basic solution which, when added in sufficient quantity, neutralises the effect of the acid.
3. When the acid is completely neutralised, the solution is no longer acidic, causing the colour of the indicator to change from red to blue.

**Answer:** There is a change in colour because lime water (a base) neutralises the acid present in the solution, making it no longer acidic.

> Common mistake: Confusing neutralisation with dilution.

## Let Us Enhance Our Learning

### Question 1

*1 mark · MCQ*

A solution turns the red litmus paper to blue. Excess addition of which of the following solution would reverse the change?

- Lime water
- Baking soda
- Vinegar
- Common salt solution

**Solution**

1. A solution that turns red litmus paper to blue is basic in nature.
2. To reverse this change, an acidic solution is required to neutralise the base, and among the choices, vinegar is acidic.

**Answer:** (iii) Vinegar

> Common mistake: Choosing lime water or baking soda, which are basic and will not reverse the colour change to red.

### Question 2

*1 mark · MCQ*

You are provided with three unknown solutions labelled A, B, and C, but you do not know which of these are acidic, basic, or neutral. Upon adding a few drops of red litmus solution to solution A, it turns blue. When a few drops of turmeric solution are added to solution B, it turns red. Finally, after adding a few drops of red rose extract to solution C, it turns green. Based on the observations, which of the following is the correct sequence for the nature of solutions A, B, and C?

- Acidic, acidic, and acidic
- Neutral, basic, and basic
- Basic, basic, and acidic
- Basic, basic, and basic

**Solution**

1. Solution A turns red litmus blue, which shows it is basic.
2. Solution B turns turmeric solution red, which shows it is basic.
3. Solution C turns red rose extract green, which shows it is basic.
4. Therefore, all three solutions are basic in nature.

**Answer:** (iv) Basic, basic, and basic

> Common mistake: Assuming different indicators always test for different natures instead of knowing specific indicator colour changes.

### Question 3

*3 marks · Short answer*

Observe and analyse Figs. 2.13, 2.14, and 2.15, in which red rose extract paper strips are used. Label the nature of solutions present in each of the containers.

**Part (i)**

1. Observe Fig. 2.13 where the red rose extract paper strip turns green.
2. Red rose extract gives a green colour in basic solutions.
3. Therefore, the solution in Fig. 2.13 is basic in nature.

Answer (i): Basic

**Part (ii)**

1. Observe Fig. 2.14 where the red rose extract paper strip shows no change in colour.
2. Neutral solutions do not change the colour of the red rose extract indicator.
3. Therefore, the solution in Fig. 2.14 is neutral in nature.

Answer (ii): Neutral

**Part (iii)**

1. Observe Fig. 2.15 where the red rose extract paper strip turns red.
2. Red rose extract gives a red colour in acidic solutions.
3. Therefore, the solution in Fig. 2.15 is acidic in nature.

Answer (iii): Acidic

**Answer:** Fig. 2.13 is basic, Fig. 2.14 is neutral, and Fig. 2.15 is acidic.

> Common mistake: Confusing the colours of red rose extract in acidic and basic solutions.

### Question 4

*3 marks · Short answer*

A liquid sample from the laboratory was tested using various indicators. Based on the tests, identify the acidic or basic nature of the liquid and justify your answer.

**Solution**

1. The liquid sample showed no change with red litmus paper, turned blue litmus paper to red, and showed no change in colour with turmeric.
2. Since blue litmus turns red, the liquid is acidic in nature.
3. Turmeric and red litmus show no change in acidic solutions, which confirms the sample is an acid.

**Answer:** The liquid sample is acidic in nature because it turns blue litmus red while having no effect on red litmus and turmeric.

> Common mistake: Forgetting that turmeric does not change colour in acidic solutions.

### Question 5

*3 marks · Short answer*

Manya is blindfolded. She is given two unknown solutions to test and determine whether they are acidic or basic. Which indicator should Manya use to test the solutions and why?

**Solution**

1. Manya is blindfolded and cannot see visual indicators like litmus or turmeric paper change colours.
2. She should use an olfactory indicator, which is a substance whose odour changes in acidic or basic media.
3. By smelling the change in odour upon adding the unknown solutions, she can easily determine whether they are acidic or basic.

**Answer:** Manya should use an olfactory indicator because its odour changes in acidic or basic solutions, allowing her to test them without seeing.

> Common mistake: Recommending visual indicators like litmus paper which require sight to observe colour changes.

### Question 6

*3 marks · Short answer*

Could you suggest various materials which can be used for writing the message on the white sheet of paper (given at the beginning of the chapter) and what could be in the spray bottle? Make a table of various possible combinations and the colour of the writing obtained.

**Solution**

1. The white sheet of paper can be coated with an indicator like turmeric paste, and the spray bottle can contain a basic solution like soap solution.
2. Alternatively, the paper can be written on with a basic solution and sprayed with a natural indicator extract like red rose or turmeric.
3. When soap solution is applied on turmeric paper, it turns red, making the secret message visible.

**Answer:** Turmeric paper can be used with a soap solution spray, producing red writing on a yellow background.

> Common mistake: Using substances that do not produce a visible colour change with the chosen indicator.

### Question 7

*3 marks · Short answer*

Grape juice was mixed with red rose extract; the mixture got a tint of red colour. What will happen if baking soda is added to this mixture? Justify your answer.

**Solution**

1. Grape juice is acidic, so mixing it with red rose extract gives a red colour.
2. Baking soda is basic in nature.
3. When baking soda is added, it neutralises the acid and changes the colour of the mixture to green.

**Answer:** The mixture will turn green due to the basic nature of baking soda.

> Common mistake: Confusing the indicator colour for basic medium as red instead of green.

### Question 8

*3 marks · Short answer*

Keerthi wrote a secret message to her grandmother on her birthday using orange juice. Can you assist her grandmother in revealing the message? Which indicator would you use to make it visible?

**Solution**

1. Orange juice contains citric acid and is acidic in nature.
2. When applied on paper, the written message is initially colourless or invisible.
3. An indicator like turmeric solution, turmeric paper, or red rose extract can be used to reveal the message by showing a distinct colour change.

**Answer:** Turmeric solution or turmeric paper can be used to reveal the message.

> Common mistake: Stating that water can reveal the message instead of an indicator.

### Question 9

*3 marks · Short answer*

How can natural indicators be prepared? Explain by giving an example.

**Solution**

1. Natural indicators can be prepared by extracting coloured pigments from plants like flowers, fruits, or vegetables.
2. For example, to prepare red rose extract, take a fistful of fallen rose petals, crush them in a mortar and pestle, and place them in a glass tumbler.
3. Pour hot water over the petals, cover it for 5 to 10 minutes until the water becomes coloured, and filter the liquid to get the red rose extract.

**Answer:** Natural indicators are prepared by crushing plant parts and extracting their coloured juice using hot water.

> Common mistake: Plucking fresh flowers instead of using fallen petals as advised in the textbook.

### Question 10

*3 marks · Short answer*

Three liquids are given to you. One is vinegar, another is a baking soda solution, and the third is a sugar solution. Can you identify them only using turmeric paper? Explain.

**Solution**

1. Yes, the three liquids can be identified using turmeric paper because turmeric paper turns red in basic solutions and remains unchanged in acidic and neutral solutions.
2. When drops of the three liquids are put on turmeric paper, vinegar (acid) and sugar solution (neutral) will show no colour change, whereas baking soda solution (base) will turn the paper red.
3. To distinguish between vinegar and sugar solution, we cannot use turmeric paper alone since it does not differentiate between acidic and neutral substances.

**Answer:** Baking soda solution is identified by turning turmeric paper red, while vinegar and sugar solution cannot be distinguished from each other using only turmeric paper.

> Common mistake: Assuming turmeric paper can differentiate between acidic and neutral substances.

### Question 11

*3 marks · Short answer*

The extract of red rose turns the liquid X to green. What will the nature of liquid X be? What will happen when excess of amla juice is added to liquid X?

**Solution**

1. Red rose extract gives a green colour in a basic solution, so liquid X is basic in nature.
2. Amla juice contains ascorbic acid and citric acid, making it acidic in nature.
3. When excess amla juice is added to liquid X, it neutralises the base and eventually turns the mixture red.

**Answer:** Liquid X is basic in nature, and adding excess amla juice neutralises it, changing the colour to red.

> Common mistake: Forgetting that addition of excess acid will revert the indicator colour back to the acidic shade.

### Question 12

*3 marks · Short answer*

Observe and analyse the information given in the following flowchart. Complete the missing information.

**Solution**

1. The soil can be acidic in nature or basic in nature.
2. Any suitable acid-base indicator or soil testing method can be used to test the nature of the soil.
3. Acidic soil can be treated with lime, and basic soil can be treated with organic matter like manure or composted leaves.

**Answer:** Missing information: Soil can be acidic or basic; indicator is a natural/synthetic indicator; acidic soil is treated with lime and basic soil with manure.

> Common mistake: Confusing the correct neutralising agent for acidic and basic soils.

## Dive Deeper

### Question 1

*3 marks · Short answer*

Aman accidentally spilt vinegar on some pieces of an eggshell or marble and noticed bubbling. He then poured a soap solution on another piece of eggshell or marble, but no bubbles appeared. Why did bubbles occur with vinegar but not with soap solution?

**Solution**

1. Vinegar is an acid which reacts with the calcium carbonate present in eggshells and marble to release carbon dioxide gas, causing bubbling.
2. Soap solution is basic in nature and does not react with calcium carbonate.
3. Therefore, bubbles of carbon dioxide gas are observed only with vinegar and not with soap solution.

**Answer:** Bubbles occurred because vinegar is an acid that reacts with calcium carbonate in eggshells to release carbon dioxide gas, whereas the soap solution is basic and does not react.

> Common mistake: Confusing the reaction of acids with carbonates as a neutralisation reaction instead of a gas-evolving reaction.

## Exploratory Projects

### Question 1

*Activity*

Create rangoli using acidic or basic substances and natural indicators.

**Solution**

1. Take a rangoli base or paper sheet prepared with a natural indicator such as turmeric paper or flower extract.
2. Apply acidic or basic solutions like soap solution or lemon juice using a dropper or brush to create patterns.
3. Observe the colour changes produced due to the acid-base indicator reaction.

**Answer:** A colourful rangoli pattern formed by colour changes of indicators with acidic and basic substances.

### Question 2

*3 marks · Short answer*

You may discuss in your class the acidic, basic, or neutral nature of water obtained from various sources. You may like to test the water samples available from sources such as rain, taps, rivers, etc.

**Solution**

1. Collect water samples from different sources such as rain, tap water, and river water in clean containers.
2. Test each water sample using drops of blue and red litmus paper or natural indicators like turmeric or red rose extract.
3. Record the observations: rain water is generally slightly acidic due to dissolved carbon dioxide, tap water is usually neutral, and river water can vary depending on dissolved minerals or pollutants.

**Answer:** Rain water is slightly acidic, while tap water and pure water are generally neutral in nature.

> Common mistake: Assuming all natural water sources are strictly neutral without testing.

### Question 3

*Activity*

Collect a soil sample of your area and find out whether it is acidic, basic, or neutral in nature.

**Solution**

1. Collect a small soil sample from the local area and mix it with a little distilled water in a clean container to make a suspension.
2. Allow the soil particles to settle down and filter the clear liquid extract.
3. Test the filtered soil extract using red and blue litmus paper or natural indicators to determine if it is acidic, basic, or neutral.

**Answer:** The soil sample is tested with indicators to find its acidic, basic, or neutral nature.

## Frequently asked questions

### How many total questions are there in NCERT Solutions for Class 7 Science Chapter 2 Exploring Substances: Acidic, Basic, and Neutral?

This chapter contains a total of 39 questions distributed across various activities, the holistic lens, fascinating facts, let us enhance our learning, dive deeper, and exploratory projects. You can find SwaVid's free PDF and step-by-step solutions for all these questions on this page only.

### Which topics are covered in the questions for Class 7 Science Chapter 2?

The questions cover concepts such as litmus paper colour changes, common acids in edible substances, natural indicators like turmeric and red rose extract, olfactory indicators, and neutralisation reactions. SwaVid's free PDF and step-by-step solutions on this page only provide detailed explanations for all these topics.

### Which are considered the hardest question types in this chapter and how should I approach them?

Questions involving practical applications, such as the reaction of acids with metal carbonates or preparing natural indicators, can be challenging because they require clear observation and chemical understanding. To approach them, break down the experiment steps and relate them to the core properties of acids, bases, and neutralisation as explained in SwaVid's free PDF and step-by-step solutions on this page only.

### How can I write answers to score full marks in Class 7 Science Chapter 2 examinations?

To score full marks, write precise definitions, mention specific colour changes for indicators accurately, and state balanced scientific terms for neutralisation and olfactory indicators. SwaVid's free PDF and step-by-step solutions on this page only provide structured answers that help you present your points clearly.

### Is the free PDF for Class 7 Science Chapter 2 available for download?

Yes, complete solutions aligned with the new NCERT book for the 2026-27 session are easily accessible. You can download SwaVid's free PDF and step-by-step solutions on this page only to help with your daily revision.

## Related pages

- [Exercise 2.1 solutions](https://www.swavid.com/science/class/7/chapter/exploring-substances-acidic-basic-and-neutral/ncert-solutions/exercise-2-1)
- [Exercise 2.2 solutions](https://www.swavid.com/science/class/7/chapter/exploring-substances-acidic-basic-and-neutral/ncert-solutions/exercise-2-2)
- [Exercise 2.4 solutions](https://www.swavid.com/science/class/7/chapter/exploring-substances-acidic-basic-and-neutral/ncert-solutions/exercise-2-4)
- [Exercise 2.5 solutions](https://www.swavid.com/science/class/7/chapter/exploring-substances-acidic-basic-and-neutral/ncert-solutions/exercise-2-5)
- [Exercise 2.6 solutions](https://www.swavid.com/science/class/7/chapter/exploring-substances-acidic-basic-and-neutral/ncert-solutions/exercise-2-6)
- [Exercise 2.7 solutions](https://www.swavid.com/science/class/7/chapter/exploring-substances-acidic-basic-and-neutral/ncert-solutions/exercise-2-7)
- [Class 7 Science chapters](https://www.swavid.com/science/class/7)

Solutions written by SwaVid, a personal AI tutor for Class 6 to 10 Maths and Science. Practise this chapter free: https://www.swavid.com/start/student