CBSE Class 10 Science Acids Bases and Salts MCQs Set 07

Question. Sodium hydrogencarbonate when added to acetic acid evolves a gas. Which of the following statements is 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)
(d) (i) and (iv)

Answer: B

Question. Human body works within the pH range of
(a) 7.0 to 7.8
(b) 4.5 to 5.6
(c) 13.0 to 14.0
(d) 1.2 to 2.2

Answer: A

Question. The acid having highest hydrogen ion concentration is one with
(a) pH = 2.5
(b) pH = 1.8
(c) pH = 7
(d) pH = 10

Answer: B

Question. The pH of the gastric juices released during digestion is:
(a) less than 7
(b) more than 7
(c) equal to 7
(d) equal to 0 

Answer: A

Question. The correct statement regarding universal indicator is
(a) it is an indicator having pH = 7
(b) it gives blue colour at pH = 3
(c) it becomes colourless at pH = 7
(d) it gives orange colour at pH = 3

Answer: D

Question. Which of the following will conduct electricity?
(a) Glucose solution
(b) Ethanol solution
(c) Acetic acid solution
(d) Dry HCl(g)

Answer: C

Question. Which of the following is (are) true when HCl(g) is passed through water?
(i) It does not ionise in the solution as it is a covalent compound.
(ii) It ionises in the solution.
(iii) It gives both hydrogen and hydroxyl ion in the solution.
(iv) It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule.
(a) (i) only
(b) (iii) only
(c) (ii) and (iv)
(d) (iii) and (iv)

Answer: C

Question. What happens when a solution of an acid is mixed with a solution of a base in a test tube?
(i) Temperature of the solution decreases
(ii) Temperature of the solution increases
(iii) Temperature of the solution remains the same
(iv) Salt formation takes place
(a) (i) and (iv)
(b) (i) and (iii)
(c) (ii) only
(d) (ii) and (iv)

Answer: D

Question. Tooth enamel is made up of
(a) calcium phosphate
(b) calcium carbonate
(c) calcium oxide
(d) potassium

Answer: A

Question. Rain is called acid rain when its:
(a) pH falls below 7
(b) pH falls below 6
(c) pH falls below 5.6
(d) pH is above 7

Answer: C

Question. 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)
(d) (i), (iii) and (iv)

Answer: C

Question. Which of the following salts does not contain water of crystallisation?
(a) Blue vitriol
(b) Baking soda
(c) Washing soda
(d) Gypsum

Answer: B

Question. You are having five solutions A, B, C, D and E with pH values as follows:
A = 1.8, B = 7, C = 8.5, D = 8 and E = 5
Which solution would be most likely to liberate hydrogen with magnesium powder?
(a) Solution A and B
(b) Solution A
(c) Solution C
(d) All of the above

Answer: B

Question. The pH of a solution is 4.0. What should be the change in the hydrogen ion concentration of the solution, if its pH is to increased to 5.0.
(a) decreases to 1/10 of its original concentration
(b) halved
(c) doubled
(d) increases by 10 times

Answer: A

Question. When hydrogen chloride gas is prepared on a humid day, the gas is usually passed through the guard tube containing calcium chloride. The role of calcium chloride taken in the guard tube is to
(a) absorb the evolved gas
(b) moisten the gas
(c) absorb moisture from the gas
(d) absorb Cl– ions from the evolved gas

Answer: C

Question. What is formed when zinc reacts with sodium hydroxide?
(a) Zinc hydroxide and sodium
(b) Sodium zincate and hydrogen gas
(c) Sodium zinc-oxide and hydrogen gas
(d) Sodium zincate and water

Answer: B

Question. 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.
(d) Neutralise the acid with a strong alkali.

Answer: B

Question. A basic solution could have a pH of
(a) 1
(b) 11
(c) 7
(d) 2

Answer: D

Question. Which of the following will turn red litmus blue
(a) Mg(OH)²
(b) Citric acid
(c) Carbonic acid
(d) Acetic acid

Answer: A

Question. When small amount of acid is added to water, the phenomenon which occur are
(A) Dilution
(B) Neutralisation
(C) Formation of H₃O+
(D) Salt formation
The correct statements are
(a) (A) and (C)
(b) (B) and (D)
(c) (A) and (B)
(d) (C) and (D)

Answer: A

Question. 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
(d) Hydrochloric acid < Water < Acetic acid

Answer: A

Question. Fruit juices, such as orange juice, contain
(a) boric acid
(b) citric acid
(c) sulphuric acid
(d) nitric acid

Answer: B

Question. In general, salts
(a) are ionic compounds.
(b) contain hydrogen ions.
(c) contain hydroxide ions.
(d) turn blue litmus red.

Answer: A

Question. A base can be prepared by the reaction between
(a) an active non-metal and water.
(b) a gas and water.
(c) a sulphide and water.
(d) an active metal and water.

Answer: D

Question. What is the use of washing soda?
(a) To lower the temperature of the water
(b) To change the state of water
(c) To make the water alkaline
(d) To remove the permanent hardness of water

Answer: D

In the following question, a statement of Assertion (A) is followed by a statement of Reason (R). Answer these questions by selecting appropriate option given below:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A)
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true.

Question. Assertion (A): When common salt is kept open, it absorbs moisture from the air.
Reason (R): Common salt contains magnesium chloride.

Answer: A

Question. Assertion (A): Baking soda creates acidity in the stomach.
Reason (R): Baking soda is alkaline.

Answer: D

Question. Assertion (A): On adding H₂SO₄ to water the resulting aqueous solution get corrosive.
Reason (R): Hydronium ions are responsible for corrosive action.

Answer: A

Question. Assertion (A): H₂CO₃ is a strong acid.
Reason (R): A strong acid dissociates completely or almost completely in water.

Answer: D

Question. Assertion (A): Ammonia solution is an alkali.
Reason (R): Ammonia solution turns blue litmus paper red.

Answer: C

Question. Assertion (A): Sodium hydroxide reacts with zinc to produce hydrogen gas.
Reason (R): Acids reacts with active metals to produce hydrogen gas.

Answer: B

Question. Assertion (A): When zinc is added to dilute hydrochloric acid, hydrogen is given off.
Reason (R): Hydrogen chloride molecules contain hydrochloric acid and hydrogen atoms.

Answer: B

Question. Assertion (A): To dilute concentrated sulphuric acid water is added to the acid slowly.
Reason (R): A lot of heat energy will be given out in the dilution of concentrated sulphuric acid.

Answer: A

Question. Assertion (A): HCl produces hydronium ions (H₃O⁺) and chloride ions (Cl^–) in aqueous solution.
Reason (R): In presence of water, basic give H+ ions.

Answer: C

Question. Assertion (A): In water, Hydrochloric acid behaves as a weak monobasic acid.
Reason (R): In water, Hydrochloric acid acts as a proton donor.

Answer: D