Acids, Bases and Salts

CBSE Class 10 Science · every board question from this chapter, 2023–2026

• Tomato is a natural source of which acid?2026
• Tamarind is a natural source of which acid?2026
• Rain water is called 'acid rain' when its:2026
• Which of the following compounds is used for removing permanent hardness of water?2026
• To a small amount of copper oxide in a beaker, when we add dilute hydrochloric acid slowly with stirring, the change in the…2026
• Which one of the following can be used as an acid-base indicator by a visually impaired (blind) student?2026
• A metal carbonate reacts with a solution X which forms a salt, water and a gas Y. What are X and Y?2026
• An aqueous solution turns red litmus blue. Excess addition of which of the following solution would reverse the change?2026
• In the following diagram, if acetic acid of same concentration is taken in place of dilute sulphuric acid, then2026
• Magnesium ribbon burns with a dazzling white flame and changes into a white powder as shown in the diagram given below: The…2026
• Study the following table and select the correct option: (Salt, Acid used, Base used, Nature of Salt)2026
• Baking powder is a mixture of:2026
• Four solutions, namely fructose, ethanol, hydrochloric acid and sodium hydroxide filled in four separate beakers are connected…2026
• Which gas is evolved when magnesium metal reacts with very dilute HNO_3?2026
• Which one of the following chemicals is used in soda-acid fire- extinguishers?2026
• How will you protect yourself from the heat generated while diluting a concentrated acid?2026
• Define the following terms: (i) Olfactory indicator (ii) Water of crystallization2026
• How is a universal indicator obtained? How is the wide range of pH of solution tested by it?2026
• Why does one feels pain and irritation when stung by honey-bee? Rubbing of baking soda on the stung area gives relief. How?2026
• How is tooth decay related to pH? How can it be prevented?2026
• Show the formation of NaCl by transfer of electrons. Why does solid NaCl not conduct electricity? [Atomic number: Na=11, Cl=17 ]2026
• A compound 'A' is used in soda-lime fire-extinguisher and decomposes on heating to form compound 'B'. Compound 'B' is used for…2026
• Write the preparation of Baking soda. How does it help in making cakes soft and spongy?2026
• Write the balanced chemical equations involved in the preparation of Bleaching powder Baking soda2026
• Explain chlor-alkali process with chemical equation. Name the products formed at anode and cathode. OR Write the preparation of…2026
• Attempt either or: Give reasons: 3 × 1=3 (i) For dilution of an acid, acid is added into water and not water into acid. (ii) Dry…2026
• Give the chemical name and formula of Plaster of Paris. Write the chemical equation of its preparation. Give any two uses of it.…2026
• Which of the given option represents a family of salts?2025
• In order to prepare dry hydrogen chloride gas in humid atmosphere the gas produced is passed through a guard tube (drying tube)…2025
• The formula of washing soda is2025
• You have three aqueous solutions A, B and C as given below: A - Potassium nitrate B - Ammonium chloride C - Sodium carbonate The…2025
• The warning sign shown in the given figure must invariably be displayed/pasted on the containers which contain hydroxide of:2025
• In one formula unit of salt 'X', seven molecules of water of crystallisation are present. The salt 'X' is:2025
• The following table shows the pH values of four solutions A, B, C and D on a pH scale: The solutions A, B, C and D respectively…2025
• The chlorine produced during the electrolysis of brine solution is used in the manufacture of:2025
• A common feature observed in the crystals of washing soda, copper sulphate, gypsum and ferrous sulphate is that all2025
• The body of human beings works within the pH range of:2025
• Consider the following reactions: (i) Dilute hydrochloric acid reacts with sodium hydroxide. (ii) Magnesium oxide reacts with…2025
• Tooth enamel is made up of calcium hydroxyapatite (a crystalline form of calcium phosphate). This chemical starts corroding in…2025
• Juice of tamarind turns blue litmus to red. It is because of the presence of a chemical compound called2025
• The nature of aqueous solution of potassium nitrate is:2025
• The water of crystallization is present in (i) Bleaching Powder (ii) Plaster of Paris (iii) Washing Soda (iv) Baking Soda2025
• Assertion: Hydrogen gas is not evolved when a metal reacts with nitric acid. Reason (R): Nitric acid is a strong reducing agent…2025
• Assertion: Concentrated nitric acid is diluted by adding water slowly to acid with constant stirring. Reason (R): Concentrated…2025
• A crystalline substance of green colour 'X' emits gases of characteristic odour when heated over a flame. It first loses water…2025
• Write the formula of the ions which (i) acids, and (ii) bases generate in water solutions. Dry HCl gas does not change the colour…2025
• A chemical compound 'X' is used to bleach washed clothes in laundry as well as to make drinking water free from germs. Identify…2025
• Giving reason, state the advantage of using baking powder over baking soda for the preparation of bread or cakes.2025
• Write chemical formula of washing soda. How is it obtained from baking soda? List two uses of washing soda.2025
• In an experiment a student dipped pH papers in four different solutions A, B, C and D and reported his observation as given…2025
• Common salt is an important raw material for various chemicals of daily use. State in brief the method of preparation of (i)…2025
• State the chemical property in each case on which the following uses of baking soda are based upon: (i) as an anti-acids (ii) as…2025
• Acid-base indicators can be used to distinguish between an acid and a base. Universal indicator, a mixture of several indicators,…2025
• Seawater contains many salts dissolved in it. Common salt is separated from these salts. Deposits of solid salt are also found in…2025
• Common salt is a very important chemical compound for our daily life. It's chemical name is sodium chloride and it is used as a…2025
• Identify the product 'X' obtained in the following chemical reaction: CaCO_3 →Δ^′ X^′+CO_22024
• Solid Calcium oxide reacts vigorously with water to form Calcium hydroxide accompanied by the liberation of heat. From the…2024
• Select a pair of natural indicator from the following:2024
• An aqueous solution of a salt turns blue litmus to red. The salt could be the one obtained by the reaction of:2024
• An aqueous solution 'A' turns phenolphthalein solution pink. When another aqueous solution 'B' is added to the pink solution, the…2024
• A chemical compound used in glass, soap and paper industries is2024
• The salt present in tooth enamel is:2024
• Four solutions, namely glucose, alcohol, hydrochloric acid and sulphuric acid filled in four separate beakers are connected one…2024
• An aqueous solution of sodium chloride is prepared in distilled water. The pH of this solution is:2024
• The oxide which can react with HC l as well as KOH to give corresponding salt and water is2024
• Consider the following cases: CaSO_4+Al → CuSO_4+Ca → FeSO_4+Cu → ZnSO_4+Mg → The cases in which new products will form are -2024
• Consider the following compounds: FeSO_4; CuSO_4; CaSO_4; Na_2 CO_3 The compound having maximum number of water of…2024
• Tooth decay begins at the pH of:2024
• 1 gram of solid sodium chloride was taken in a clean and dry test tube and concentrated sulphuric acid was added to it. (i) Name…2024
• A spatula full of sodium carbonate is taken in a test tube and 2 mL of dilute ethanoic acid is added to it. Write a chemical…2024
• A small amount of copper oxide was taken in a beaker and dilute hydrochloric acid was added with continuous stirring of the…2024
• Write the common name and the chemical name of the compound CaSO_4 · 1/2 H_2 O. Write the method of its preparation. Give…2024
• (i) The pH of a sample of tomato juice is 4.6. How is this juice likely to be in taste? Give reason to justify your answer. (ii)…2024
• A compound which is prepared from gypsum has the property of hardening when water is mixed in right quantity with it: (i) Write…2024
• (i) Five solutions A, B, C, D and E when tested with pH paper showed pH as 4, 1, 13, 7 and 10 respectively. Which solution is:…2024
• A few crystals of ferrous sulphate were taken in a dry boiling tube and heated. Tiny water droplets were observed in the tube…2024
• Explain chlor-alkali process and write balanced chemical equations for the reactions that occur. Name the gases obtained at the…2024
• Salts play a very important role in our daily life. Sodium chloride which is known as common salt is used almost in every…2024
• In the experimental setup given below, it is observed that on passing the gas produced in the reaction in the solution 'X' the…2023
• When Sodium bicarbonate reacts with dilute hydrochloric acid, the gas evolved is:2023
• A solution turns the colour of turmeric to reddish brown. If the same solution is poured on universal indictor, its colour would…2023
• Few drops of aqueous solution of ammonium chloride are put on a universal indicator paper. The paper turns pink. Study the…2023
• In the given experimental set-up, if the experiment is carried out separately with each of the following solutions the cases in…2023
• Which of the following gives the correct increasing order of acidic strength?2023
• The table below has information regarding pH and the nature (acidic/basic) of four different solutions. Which one of the options…2023
• Fresh milk has a pH of 6. To delay its curdling, a chemical substance is added to it, which is:2023
• Two salts 'X' and 'Y' are dissolved in water separately. When phenolphthalein is added to these two solutions, the solution 'X'…2023
• There are four solutions A, B, C, and D with pH values as follows: Which solution(s) would liberate hydrogen gas with zinc?2023
• Sodium hydroxide is termed an alkali while Ferric hydroxide is not because:2023
• Select washing soda from the following:2023
• The name of the salt used to remove permanent hardness of water is:2023
• Select the correct option from the following: Salt, Parent acid, Parent base, Nature of salt2023
• Assertion: It is advised that while diluting an acid one should add water to acid and not acid to water keeping the solution…2023
• (i) A compound 'X' which is prepared from gypsum has the property of hardening when mixed with proper quantity of water. Identify…2023
• On heating 'X' at 373 K, it loses water molecules and becomes 'Y'. 'Y' is a substance which doctors use for supporting fractured…2023
• A student took a small amount of copper oxide in a conical flask and added dilute hydrochloric acid to it with constant stirring.…2023
• A knife which is used to cut a fruit was immediately dipped into water containing drops of blue litmus solution. If the colour of…2023
• On heating 'X' at 373 K, it loses water molecules and becomes 'Y'. 'Y' is a substance which doctors use for supporting fractured…2023
• Write a balanced equation to show the reaction that occurs when a piece of aluminium is dipped in a dilute solution of (i)…2023
• A chemical compound X is used in glass, soap and paper industries. On treatment with ethanoic acid, it forms salt, water and…2023
• Consider the following salts: (i) YCl (ii) NH_4 X (iii) ZCO_3 What would be the pH of the salt solution if in YCl, Y is sodium?…2023
• Sometimes the pH of our mouth gets lower than 5 · 5. Why? A basic salt 'X' is obtained by heating baking soda followed by…2023
• (i) What property do acids and bases have in common? Explain it with an example. (ii) A compound which is prepared from gypsum…2023
• (i) Suggest a safe procedure of diluting a strong concentrated acid. (ii) Name the salt formed when sulphuric acid is added to…2023
• Write the chemical composition of tooth enamel. Under what conditions of pH it starts corroding? Explain the reason of tooth…2023
• How is a universal indicator better than litmus solution? State two features of pH scale. Why should we not add water to a…2023
• The teacher while conducting practicals in the laboratory divided the students into three groups and gave them various solutions…2023

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