Acids, Bases and Salts: Class 10 Science Q&A · Page 2
77 free answers on Acids, Bases and Salts (Science) for Class 10 students, across CBSE, ICSE and State boards.
Question & Answer
Questions
- ScienceClass 10CBSE
Which of the following statements is not correct? (a) All metal carbonates react with acid to give a salt, water and carbon dioxide (b) All metal oxides react with water to give salt and acid (c) Some metals react with acids to give salt and hydrogen (d) Some non metal oxides react with water to form an acid
Soln: Answer is (b) All metal oxides react with water to give salt and acid Explanation: Metal oxides are basic in nature hence they give alkaline solution when dissolved in water.
- ScienceClass 10CBSE
Which among the following is not a base? (a) NaOH (b) KOH (c) NH4OH (d) C2H5 OH
Soln: Answer is (d) C2H5 OH Explanation: C2H5 OH is an alcohol not a base
- ScienceClass 10CBSE
Which of the following is not a mineral acid? (a) Hydrochloric acid (b) Citric acid (c) Sulphuric acid Nitric acid
Soln: Answer is (b) Citric acid Explanation: Citric acid is the organic acid hence it is the answer
- ScienceClass 10CBSE
Which of the following is used for dissolution of gold? (a) Hydrochloric acid (b) Sulphuric acid (c) Nitric acid Aqua regia
Solution: Answer is (d) Aqua regia Explanation: Gold is a nobel metal which will not react even with strong acids, hence aqua regia which is a mixture of Nitric and Hydro chloric acid in the ratio 1:3 is used for dissolution of gold.
- ScienceClass 10CBSE
Which of the following is acidic in nature? (a) Lime juice (b) Human blood (c) Lime water Antacid
Soln: Answer is (a) Lime juice Explanation: Lime juice has citric acid in it. Hence it is acidic in nature.
- ScienceClass 10CBSE
Which of the following substance will not give carbon dioxide on treatment with dilute acid? (a) Marble (b) Limestone (c) Baking soda Lime
Soln: Answer is (d) Lime Explanation: Marble, Limestone and baking soda have carbonates which produces CO2 gas. Lime contains Hydroxide which will not produce CO2.
- ScienceClass 10CBSE
Which one of the following can be used as an acid–base indicator by a visually impared student? (a) Litmus (b) Turmeric (c) Vanilla essence Petunia leaves
Soln: Answer is (c) Vanilla essence Explanation: Vanilla essence can be used as an olfactory indicator hence it can be used as acid base indicator by visually impaired students.
- ScienceClass 10CBSE
Which of the following phenomena occur, when a small amount of acid is added to water? (i) Ionisation (ii) Neutralisation (iii) Dilution (iv) Salt formation (a) (i) and (ii) (b) (i) and (iii) (c) (ii) and (iii) (ii) and (iv)
Soln: Answer is (b) (i) and (iii)
- ScienceClass 10CBSE
The pH of the gastric juices released during digestion is (a) less than 7 (b) more than 7 (c) equal to 7 equal to 0
Soln: Answer is (a) less than 7 Explanation: The PH is acidic to below 7 to ensure easy breakdown of food particles. PH of stomach juices is usually 3.
- ScienceClass 10CBSE
Which of the following statements is correct about an aqueous solution of an acid and of a base? (i) Higher the pH, stronger the acid (ii) Higher the pH, weaker the acid (iii) Lower the pH, stronger the base (iv) Lower the pH, weaker the base (a) (i) and (iii) (b) (ii) and (iii) (c) (i) and (iv) (ii) and (iv)
Soln: Answer is (d) (ii) and (iv) Explanation: On a PH scale acids are those whose PH is below 7 lower is the PH stronger will be acid and similarly Bases are those whose PH is more than 7. Higher is the PH strong will be acid.
- ScienceClass 10CBSE
To protect tooth decay we are advised to brush our teeth regularly. The nature of the tooth paste commonly used is (a) acidic (b) neutral (c) basic corrosive
Soln: Answer is c) Basic Explanation: Teeth will be acidic in nature because of bacterial activity in mouth. To neutralize the acid toothpaste will be neutral in nature.
- ScienceClass 10CBSE
One of the constituents of baking powder is sodium hydrogencarbonate, the other constituent is (a) hydrochloric acid (b) tartaric acid (c) acetic acid sulphuric acid
Soln: Answer is (b) tartaric acid Explanation: A Mild edible acid along with Sodium Hydrogen Carbonate is used to prepare baking powder. Here acetic acid or citric acid can also be used in place of tartaric acid.
- ScienceClass 10CBSE
Common salt besides being used in kitchen can also be used as the raw material for making (i) washing soda (ii) bleaching powder (iii) baking soda (iv) slaked lime (a) (i) and (ii) (b) (i), (ii) and (iv) (c) (i) and (iii) (i), (iii) and (iv)
Answer is (a) (i) and (ii)
- ScienceClass 10CBSE
Sodium hydrogencarbonate when added to acetic acid evolves a gas. Which of the following statements are true about the gas evolved? (i) It turns lime water milky (ii) It extinguishes a burning splinter (iii) It dissolves in a solution of sodium hydroxide (iv) It has a pungent odour (a) (i) and (ii) (b) (i), (ii) and (iii) (c) (ii), (iii) and (iv) (i) and (iv)
Soln: Answer is (a) (i) and (ii) Explanation: Reaction between Sodium hydrogencarbonate and acetic acid lead to evolution of carbon-di-oxide gas. CO2 turns the lime water milky and extinguish a burning splinter.
- ScienceClass 10CBSE
1. If a few drops of a concentrated acid accidentally spills over the hand of a student, what should be done? (a) Wash the hand with saline solution (b) Wash the hand immediately with plenty of water and apply a paste of sodium hydrogencarbonate (c) After washing with plenty of water apply solution of sodium hydroxide on the hand Neutralise the acid with a strong alkali
Soln: Answer is (b) Wash the hand immediately with plenty of water and apply a paste of sodium hydrogencarbonate Explanation: Washing affected hand with plenty of water will reduce the concentration of the acid. Remaining traces of the acid can be neutralized by applying a paste of Hydrogen carbonate which is basic in nature. Though NaOH is also a base but it is corrosive in nature hence it is not used to neutralize the acid.
- ScienceClass 10CBSE
Which of the following gives the correct increasing order of acidic strength (a) Water < Acetic acid < Hydrochloric acid (b) Water < Hydrochloric acid< Acetic acid (c) Acetic acid< Water < Hydrochloric acid Hydrochloric acid< Water<Acetic acid
Soln: Answer is a) Water < Acetic acid < Hydrochloric acid Explanation: Water is neutral in its pure form, Acetic acid is an organic acid which is weak in nature and Hydrochloric acid is a strong acid.
- ScienceClass 10CBSE
A sample of soil is mixed with water and allowed to settle. The clear supernatant solution turns the pH paper yellowish-orange. Which of the following would change the colour of this pH paper to greenish-blue? (a) Lemon juice (b) Vinegar (c) Common salt (d) An antacid
Soln: Answer is (d) An antacid Explanation: Sample solution turn pH paper yellowish-orange which confirms the acidic nature of the sample. In order to make the color to greenish-blue we have to add an antacid.
- ScienceClass 10CBSE
Calcium phosphate is present in tooth enamel. Its nature is (a) basic (b) acidic (c) neutral amphoteric
Soln: Answer is (a) basic Explanation: Phosphate ion present in calcium phosphate is a strong base and it form a strong salt. Hence calcium phosphate is basic in nature
- ScienceClass 10CBSE
Sodium carbonate is a basic salt because it is a salt of (a) strong acid and strong base (b) weak acid and weak base (c) strong acid and weak base weak acid and strong base
Soln: Answer is (d) weak acid and strong base Explanation: Salt formed by weak acid and strong base form strong salt. Here Sodium is a strong base and carbonate is a weak acid.
- ScienceClass 10CBSE
Which of the following salts does not contain water of crystallisation? (a) Blue vitriol (b) Baking soda (c) Washing soda (d) Gypsum
Soln: Answer is (b) Baking soda Explanation Baking sodas is white amorphous powder where as other salts given in the question are crystalline in nature.