CBSE Class 10 Chemistry Acids Base and Salts Worksheet Set D

CBSE Class 10 Chemistry Acids Base and Salts Worksheet Set D

Assertion and Reason Type MCQs :

Following questions consists of two statements – Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below:
A. Both assertion and reason are true, and reason is the correct explanation of assertion.
B. Both assertion and reason are true, but reason is not the correct explanation of assertion.
C. Assertion is true but reason is false.
D. Assertion is false and reason is true.

Question. Assertion (A): When dil. H₂SO₄ is added to zinc granules, a physical change is observed.
Reason(R): A gas is evolved which burns with ‘pop’ sound.

Answer: D

Question. Assertion (A): pH = 7 indicates pure water.
Reason(R): At the pH 7, [H⁺] = [OH^-] = 10^-7

Answer: D

Question. Assertion(A): The chemical formula of bleaching powder is CaOCl₂.
Reason(R): Chlorine gas is passed over Calcium Oxide to form bleaching powder.

Answer: A

Question. Assertion(A): NaHCO₃+ HCl = NaCl + H₂O + CO₂
Reason (R): Evolved gas catches fire immediately.

Answer: C

Question. Assertion(A): Plaster of Paris is stored in moisture proof containers.
Reason(R) : Plaster of Paris sets into a hard mass on coming in contact with water to form anhydrous Calcium Sulphate.

Answer: C

Question. Assertion(A): NH4Cl is an acidic salt.
Reason(R): NH4Cl is the salt of hydrochloric acid and ammonium hydroxide.

Answer: A

Question. Assertion(R): The compound prepared from gypsum on heating it at 373 K , is known as Plaster of Paris.
Reason(R): Plaster of Paris is used in hospitals mainly as plaster for supporting fractured bones in the right position. In dentistry, it is used for making casts.

Answer: B

Question. Assertion(A): Bleaching powder is CaOCl₂, and is prepared from chlorine and slaked lime
Reason(R): Bleaching powder can be used for bleaching, disinfecting, oxidation.

Answer: C

CASE BASED MCQs

I. There are many substances which are used to detect the solutions as acidic or basic. They are called Acid-Base indicators. Depending upon the property of the indicator, we have different groups of Acid-Base indicators. Some indicators show different colours in acidic or basic medium and some indicators give different odours in acidic and basic medium. These indicators are either extracted from the plants or synthesised in the laboratory or industry.

Question. Which one of the following can be used as an acid-base indicator by visually impaired student?
A. Turmeric
B. Hibiscus
C. Vanilla
D. Litmus

Answer: C

Question. Select the incorrect option.
Indicator Colour in acidic medium Colour in basic medium
A. Litmus (Purple) Red Blue
B. Phenolphthalein (Colourless) Pink Colourless
C. Red cabbage extract (Purple) Red Green
D. Methyl orange (Orange) Red Yellow

Answer: B

Question. Which of the following will turn red litmus blue?
A. Amla juice
B. lemon juice
C. Soft drink
D. Baking soda

Answer: D

Question. A solution turns blue litmus red, the pH of the solution is likely to be-
A. 6
B. 7
C. 8
D. 9

Answer: A

II. Tajmahal, the seventh wonder of the world, is made of white stone. This white stone contains the same substance ‘A’ that is present in chalk powder and lime-stone. It is turning yellow due to polluted air. If it is cleaned by an acidic cleaner, a gas ‘B’ is released, which when passed through a solution ‘C’, forms the same substance which is present in the white stone that was used to make Tajmahal.

Question. Solution C is-
A. CaCl₂
B. CaCO₃
C. Ca(OH)₂
D. CaSO₄

Answer: C

Question. What is the nature of the substance A?
A. Acidic
B. Basic
C. Neutral
D. None

Answer: B

Question. The substance A is-
A. Ca₃CO₂
B. CaCO₃
C. Ca(OH)₂
D. CaSO₄

Answer: B

Question. Gas B is-
A. Hydrogen
B. Nitrogen
C. Chlorine
D. Carbon di oxide

Answer: D

III. A scale for measuring hydrogen ion concentration in a solution, called pH scale has been developed. The p in pH stands for ‘potenz’ in German, meaning power. On the pH scale we can measure pH from 0 to 14. pH should be thought of simply as a number which indicates the acidic or basic nature of a solution. Higher the hydronium ion concentration, lower is the pH value.

Question. A basic solution could have a pH of-
A. 3
B. 5
C. 7
D. 9

Answer: D

Question. The table provides the pH of four solutions P, Q, R and S.
Solution pH value
P 2
Q 9
R 5
S 11
Which of the following correctly represents the solutions in increasing order of their hydronium ion concentration?
A. P > Q > R > S
B. P > S > Q > R
C. S < Q < R < P
D. S < P < Q < R

Answer: C

Question. Which one of the following will have the highest hydrogen ion concentration?
A. pH = 1.1
B. pH = 2.2
C. pH = 3.3
D. pH = 4.4

Answer: A

Question. How is the hydrogen ion concentration and pH related to each other?
A. They are inversely proportional.
B. They are directly proportional.
C. They are equal.
D. They have no relation.

Answer: A

Acids Bases And Salts

ORAL QUESTIONS – (Conversation Type)

5. a) What is washing soda?

    b) Name the process by which sodium carbonate is manufacture.

    c) What are the raw materials used in the preparation of washing soda?

    d) Sodium carbonate is obtained from another carbonate on heating. Name it.

 

6. a) Name the substance used for bleaching cotton and wood pulp in textiles.

    b) What is its chemical name?

    c) How is it manufactured?

    d) What is slaked lime?

    e) Why does bleaching powder smell of chlorine?

 

ORAL QUESTIONS

 

1. Name the acid present in lemon juice.

 

2. What is the chemical difference between washing soda and baking powder?

 

3. Name the acid present in ant sting.

 

4. What is the ideal pH of the soil for the healthy growth of a plant?

 

5. At what pH the mouth teeth start decaying?

 

6. How is pH of an acid solution affected when it is diluted?

 

7. Name the gas responsible for extinguishing fire in a soda – acid fire extinguisher.

 

8. Out of glucose and acetic acid which one will conduct electricity in water?

 

9. What is the pH of blood?

 

10. What is the chemical name of the compound which has the property of hardening when mixed with water?

 

QUIZ – WHO AM I

 

1. I can roughly measure pH value from 0 – 14.

 

2. I am called antichlor and am used to remove excess chlorine from clothes when treated with bleaching powder.

 

3. I am a product of gypsum and am used to making chalks and fire proof materials.

 

4. I am a compound of calcium and can be used for disinfecting drinking water as well as for decolourisation.

 

5. I give different smell in acid and base solution.

 

6. I am an oxide capable of showing properties for both acids and bases.

 

7. I am a covalent compound and conducts electricity in aqueous medium.

 

8. I am a salt of potassium hydroxide and nitric acid.

 

9. I am the term used when a solid becomes liquid when exposed to moist air.

 

10. I am derived from tomato and turn blue litmus into red.