76 + Interview Questions in ACID IN GENERAL AWARENESS Page 1 InterviewSolution

1.	One of the following does not inject an acidic liquid into the skini through its sting. This is:A. honey beeB. antC. waspD. nettle leaf hair
Answer» Correct Answer - C c

Discussion

2.	Wasp sting contains:A. a sugar solutionB. an acidic liquidC. a salt solutionD. an alkaline liquid
Answer» Correct Answer - D d

Discussion

3.	If someone is suffering from the problem of acidity after overeating, which of the following would you suggest as remedy? Lemon juice, Vinegar, Baking soda solution Give reason for your choice.
Answer» Baking soda solution being basic, it neutralises excess acid in the stomach

Discussion

4.	Which of the followig is treated with chlorine to obtain bleaching powder?A. `CaSO_(4)`B. `Ca(OH)_(2)`C. `Mg(OH)_(2)`D. `KOH`
Answer» Correct Answer - b

Discussion

5.	What is the common name of the compound` CaOCl_(2)`?
Answer» Bleaching powder

Discussion

6.	The metal salt A is blue in colour. When salt A is heated strongly over a burner, then a substnace B is eliminated and a white powder C is left behind. When a few drops of a liquid D are added to powder C, it becomes blue again. What could be A, B,C and D?
Answer» A is copper sulphate pentahydrate, `CuSO_(4).5H_(2)O,` B is water, `H_(2)O`, C is anhydrous copper sulphate, `CuSO_(4)`, D is water, `H_(2)O`

Discussion

7.	A white powdery substnace having strong smell of chlorine is used for disinfecting drinking water supply at waterworks. Identify the substance. Give its chemical name and write the chemical reaction for its preparation.
Answer» Bleaching powder, `CaOCl_(2)`

Discussion

8.	When a solution is added to vanilla extract, then the characteristic smell of vanilla cannot be detected. State whether the given solution is an acid or a base.
Answer» Correct Answer - Base

Discussion

9.	How is the neutralisation of a carbonate with an acid different from the neutralisation of an oxide or a hydroxide?
Answer» Neutralisation of a carbonate with an acid produces carbon dioxide gas but not with an oxide or hydroxide

Discussion

10.	Write an equation to show the reaction between Plaster of Paris and water
Answer» `underset("Plaster of Paris")(CaSO_(4) 1/2H_(2)O)+underset("Water")(1 1/2 H_(2)O)to underset ("Gypsum (sets as hard mass)")(CaSO_(4).2H_(2)O)`

Discussion

11.	What is a neutralisation reaction? Give two examples.
Answer» The reaction between an acid and a base to form salt and water is called a neutalisation reaction. That is : Acid `+` Base `to` Salt `+` Water The examples of neutralisation reactions are as follows: (i) Sodium hydroxide reacts with sulphuric acid to form sodium sulphate and water: `underset(("Base"))underset("Sodium hydroxide")(2NaOH(aq))+underset(("Acid"))underset("Sulhuric acid")(H_(2)SO_(4)(aq))tounderset(("Salt"))underset("Sodium sulphate")(Na_(2)SO_(4)(aq))+underset("Water")(2H_(2)O(l))` (ii) Magnesium hydroxide reacts with hydrochloric acid to form magnesium chloride and water: `underset(("Base"))underset("Magnesium hydroxide")(Mg(OH)_(2)(aq))+underset(("Acid"))underset("Hydrochloric acid")(2HCl(aq))to underset(("Salt"))underset("Magnesium chloride")(MgCl_(2)(aq))+underset("Water")(2H_(2)O(l))`

Discussion

12.	Rewrite the following statement by selecting the correct options:…………. is not an alkali. (a) Sodium hydroxide (b) Potassium hydroxide (c) Copper hydroxide (d) Calcium hydroxide
Answer» Copper hydroxide is not an alkali.

Discussion

13.	Which substances are produced i by neutralization process?
Answer» Salt and water are produced in the f neutralization process.

Discussion

14.	Give scientific reason:Copper and brass utensils are tinned.
Answer» Copper and brass reacts with i organic acids present in food materials and poisonous salts are formed. Tin does not react with organic acids present in food materials. Therefore, copper or brass vessels are tinned.

Discussion

15.

Distinguish between acid and alkali :Acid and Alkali.

Answer»

Acid	Alkali
1. Acid has sour taste.	1. Alkali has bitter taste.
2. Acid turns blue litmus red.	2. Alkali turns red litmus blue.
3. An acid in an aqueous solution gives H⁺ ions.	3. An alkali in an aqueous solution gives OH⁺ ions.
4. Oxides of non – metals form acids.	4. Oxides of metals form bases.

Discussion

16.	Classify the following into acidic substances, basic substances and salts. (1) Lime water, (2) soda water, (3) soap water, (4) sea water, (5) sweet limeuice, (6) sugar caneuice, (7) buttermilk, (8) a mixture of ash in water, (9) tamarind water.
Answer» a. Acidic substances: (1) Soda water, (2) sweet limeuice, (3) buttermilk, (4) tamarind water. b. Basic substances: (1) Lime water, (2) Soap water, (3) a mixture of ash in water. c. Salts: (1) Sea water, (2) sugar caneuice.

16.

Classify the following into acidic substances, basic substances and salts. (1) Lime water, (2) soda water, (3) soap water, (4) sea water, (5) sweet limeuice, (6) sugar caneuice, (7) buttermilk, (8) a mixture of ash in water, (9) tamarind water.

Answer»

a. Acidic substances: (1) Soda water, (2) sweet limeuice, (3) buttermilk, (4) tamarind water.

b. Basic substances: (1) Lime water, (2) Soap water, (3) a mixture of ash in water.

c. Salts: (1) Sea water, (2) sugar caneuice.

Discussion

17.	State true or false.(i) Oxides of metals are alkaline in nature.(ii) Salt is acidic.(iii) Metal corrodes due to salts.(iv) Salts are neutral.
Answer» (i) True. (ii) False. (Salt is neutral) (iii) False. (Acids and bases corrode metals) (iv) True. (Not all salts neutral)

17.

State true or false.(i) Oxides of metals are alkaline in nature.(ii) Salt is acidic.(iii) Metal corrodes due to salts.(iv) Salts are neutral.

Answer»

(i) True.

(ii) False. (Salt is neutral)

(iii) False. (Acids and bases corrode metals)

(iv) True. (Not all salts neutral)

Discussion

18.	Collect soil samples from your surroundings and find out whether it is acidic or alkaline or neutral?
Answer» Soil samples collected from the surroundings are acidic in nature.

Discussion

19.	Rewrite the following statement by selecting the correct option:The colour of phenolphthalein indicator in alkaline solution is …………. (a) yellow (b) green (c) orange (d) pink
Answer» The colour of phenolphthalein indicator in alkaline solution is pink.

Discussion

20.	Give scientific reason:Quicklime or slaked lime is added to the soil.
Answer» 1. When chemical fertilizers are added to the soil, the soil becomes acidic. 2. To reduce its acidity quicklime or slaked lime is added to the soil.

20.

Give scientific reason:Quicklime or slaked lime is added to the soil.

Answer»

1. When chemical fertilizers are added to the soil, the soil becomes acidic.

2. To reduce its acidity quicklime or slaked lime is added to the soil.

Discussion

21.	Find the odd one out and justify:Lime, litmus, phenolphthalein, methyl orange.
Answer» Lime. (Others are indicators.)

Discussion

22.	By squeezzing lemon on a piece of rock the gas liberated turned lime water milky. Which compound is present in the rock?
Answer» Metal carbonate is present in the rock.

Discussion

23.

Match the pairs. Group AGroup B1. Tamarinda. Acetic acid2. Curdb. Citric acid3. Lemonc. Tartaric acid4. Vinegard. Lactic acid

Answer»

Group A	Group B
1. Tamarind	c. Tartaric acid
2. Curd	d. Lactic acid
3. Lemon	b. Citric acid
4. Vinegar	a. Acetic acid

Discussion

24.	A solution turns blue litmus red. Its pH is likely to be:A. 7B. 5C. 8D. 14
Answer» Correct Answer - B b

Discussion

25.	A solution turns phenolphthalein indicator pink. The most likely pH of this solution will be:A. 6B. 4C. 9D. 7
Answer» Correct Answer - C c

Discussion

26.	The colour of methyl orange indicator in a solution in yellow. The pH of this solution is likely to be:A. 7B. less than 7C. 0D. more than 7
Answer» Correct Answer - D d

Discussion

27.	Two drinks P and Q gave acidic and alkaline reactions, respectively one has a pH value of 9?
Answer» Correct Answer - Drink Q

Discussion

28.	You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
Answer» (i). Put the red litmus paper in all the test-tubes, tuyrn by turn. The solutio which turns red litmus to blue will be a basic solution. The blue litmus paper formed here can not be used to test the acidic solution. (ii). Put the blue litmus paper (obtained above) in the remaining two test-tubes, one by one. the solution which turns the blue litmus paper to red will be the acidic solution. (iii). the solution which has no effect on any litmus paper will be neutral and hence it will be distilled water.

Discussion

29.	The pH of soil A is 7.5 while that of soil B is 4.5. Which of the two soils, A or B, should be treated powdered chalk to adjust its pH and why?
Answer» Soil B, To reduce its acidity

Discussion

30.	Name the indicator which can give us an idea of how strong or weak an acid or base is.
Answer» Universal indicator

Discussion

31.	State the names of three weak alkalis.
Answer» 1. Calcium hydroxide 2. ammonium hydroxide 3. magnesium hydroxide.

31.

State the names of three weak alkalis.

Answer»

1. Calcium hydroxide

2. ammonium hydroxide

3. magnesium hydroxide.

Discussion

32.	Rewrite the following statement by selecting the correct options:When blue litmus paper is added to NaOH, the colour of the litmus paper will be ……………. . (a) blue (b) red (c) pink (d) yellow
Answer» When blue litmus paper is added to NaOH, the colour of the litmus paper will be blue

Discussion

33.	State two acid-base indicators and mention their colour change.
Answer» Phenolphthalein and methyl orange are two acidbase indicators. Phenolphthalein is colourless in an acidic solution while it turns pink in a basic solution. Methyl orange gives orange colour with an acidic solution and yellow colour with a basic solution.

Discussion

34.

Match the following:Column ‘A’Column ‘B’1. Sodium hydroxidea. Whitewashing2. Magnesium hydroxideb. Fertilizers3. Calcium hydroxidec. Washing soap4. Ammonium hydroxided. Antacid

Answer»

Column ‘A’	Column ‘B’
1. Sodium hydroxide	c. Washing soap
2. Magnesium hydroxide	d. Antacid
3. Calcium hydroxide	a. Whitewashing
4. Ammonium hydroxide	b. Fertilizers

Discussion

35.	(a). The pH values of six solutions A to F are given below: A=0, B=11, C=6, D=3, E=13, F=8 Which of the above solutions are (i) acids (ii) alkalis? (b). Name the acids or alkalis used to make (i) can batteries (ii) explosives (iii) soaps (iv) fertilisers.
Answer» (i) Acids: A,C and D (ii) Alkalies: B,E and F

Discussion

36.	A salt whose aqueous solution will hae a pH of more than 7 will be:A. `K_(2)CO_(3)`B. `K_(2)SO_(4)`C. `NaCl`D. `NH_(4)Cl`
Answer» Correct Answer - a

Discussion

37.	Which of the following salts will give an aqueous solution having pH of almost 7?A. `NH_(4)NO_(3)`B. `NH_(4)Cl`C. `CaCl_(2)`D. `KCl`
Answer» Correct Answer - d

Discussion

38.	One of the following salts will give an alkaline solution on dissolving in water. This is:A. `Na_(2)CO_(3)`B. `Na_(2)SO_(4)`C. `NaCl`D. `(NH_(4))_(2)SO_(4)`
Answer» Correct Answer - a

Discussion

39.	The products of chlor-alkali process are:A. `NaCl,Cl_(2) and H_(2)`B. `H_(2),Cl_(2) and NaOH`C. `Cl_(2),Na_(2)CO_(3) and H_(2)O`D. `NaOH,Cl_(2) and HCl`
Answer» Correct Answer - b

Discussion

40.	Two solutions A and B have pH values of 3.0 and 9.5 respectively. Which of these will turn litmus solution from blue to red and which will turn phenolphthalein from colourless to pink?
Answer» Solution A: litmus from blue to red, Solutio B: Phenolphthalein from colourless to pink

Discussion

41.	The aqueous solution of one of the following satls will turn red litmus to blue. This salt is:A. potassium sulphateB. sodium sulphatC. sodium chloirdeD. potassium carbonate
Answer» Correct Answer - d

Discussion

42.	The salt whose aqueous solutio will turn blue litmus to red is:A. ammonium sulphateB. sodium acetateC. sodium chlorideD. potassium carbonate
Answer» Correct Answer - a

Discussion

43.	The salt whose aqueous solution will have no effect on either red litmus or blue litmus isA. potassium sulphateB. sodium carbonateC. ammonium sulphateD. sodium acetate
Answer» Correct Answer - a

Discussion

44.	Why does dry HCl gas not change the colour of the dry litmus paper?
Answer» Dry `HCl` gas does not change the colour of dry litmus paper because it has no hydrogen ions `H^(+)` (aq) ions, in it which can impart acidic properties to it.

Discussion

45.	10 mL of a solution of NaOH is found to be completely neutralised by 8 mL of a given solution of HCl. If we take 20 mL of the same solution of NaOH, the amount HCl solution (the same solution as before) required to neutralise it will beA. 4mLB. 8 mLC. 12 mLD. 16 mL
Answer» Correct Answer - D

Discussion

46.	(a). What would you expect the pH of pure water to be? (b). What colour would the universal indicator show in an aqueous solution of sugar? Why? (c). A sample of rain water turned universal indicator paper yellow. What would you expect its pH to be? Is it a strong or a weak acid?
Answer» (a) 7 (b) green, Neutral solution (c) Between 5 and 6, Weak acid

Discussion

47.	A beaker of concentrated hydrochloric acid has a pH of 1. What colour will full range universal indicator turn if it is added to this beaker? Is it a strong or a weak acid?
Answer» Red, strong acid

Discussion

48.	Five solutions A,B,C,D and E when tested with universal indicator showed pH as 4,1,11,7 and 9, respectively. Which solution is (a) neutral? (b) strongly alkaline? (c) strongly acidic? (d) weakly acidic? (e) weakly alkaline? Arrange the pH in increasing order of hydrogen-ion concentration.
Answer» (a). (i). Neutral `D(pH=7)`, (ii). Strongly alkaline (CpH=11), (iii) strongly acidic B(pH=1), (iv). Weakly acidic: A(pH=4), (v). Weakly alkaline `E(pH=9)` (b). The solution having highest pH (11) will have the minimum hydrogen ion concentration whereas. The solution having the least pH(1) will have the maximum hydrogen ion concentration So, the given solutions can be arranged in the increasing order of their hydrogen ion concentration as hollows: `underset(("pH 11"))(C)" "underset(("pH 9"))(E)" "underset(("pH 7"))(D)" "underset(("pH 4"))(A)" "underset(("pH 1"))(B)` ltb rgt `underset("Increasing order of hydrogen concentration")overset("Decreasing order of pH")to`

Discussion

49.	Te pH values of five solutions, A, B,C,D and E are given below: A 1 B 5 C 7 D 11 E 13 ltbr. Which solution is (i) weakly alkaline (ii) neutral (iii) strongly acidic (iv) strongly alkaline, and (v) weakly acidic?
Answer» (i) D (ii) C (iii) A (iv) E (v) B

Discussion

50.	What colour will universal indicator show if you add it to the following substnaces? (a). Potassium hydroxide pH=12 (b). Soda water, pH=5 (c). Sulphuric acid, pH=2.
Answer» (a). Dark purple (b). Orange yellow (c). Red

Discussion

Explore topic-wise InterviewSolutions in .

One of the following does not inject an acidic liquid into the skini through its sting. This is:A. honey beeB. antC. waspD. nettle leaf hair

Wasp sting contains:A. a sugar solutionB. an acidic liquidC. a salt solutionD. an alkaline liquid

If someone is suffering from the problem of acidity after overeating, which of the following would you suggest as remedy? Lemon juice, Vinegar, Baking soda solution Give reason for your choice.

Which of the followig is treated with chlorine to obtain bleaching powder?A. `CaSO_(4)`B. `Ca(OH)_(2)`C. `Mg(OH)_(2)`D. `KOH`

What is the common name of the compound` CaOCl_(2)`?

The metal salt A is blue in colour. When salt A is heated strongly over a burner, then a substnace B is eliminated and a white powder C is left behind. When a few drops of a liquid D are added to powder C, it becomes blue again. What could be A, B,C and D?

A white powdery substnace having strong smell of chlorine is used for disinfecting drinking water supply at waterworks. Identify the substance. Give its chemical name and write the chemical reaction for its preparation.

When a solution is added to vanilla extract, then the characteristic smell of vanilla cannot be detected. State whether the given solution is an acid or a base.

How is the neutralisation of a carbonate with an acid different from the neutralisation of an oxide or a hydroxide?

Write an equation to show the reaction between Plaster of Paris and water

What is a neutralisation reaction? Give two examples.

Rewrite the following statement by selecting the correct options:…………. is not an alkali. (a) Sodium hydroxide (b) Potassium hydroxide (c) Copper hydroxide (d) Calcium hydroxide

Which substances are produced i by neutralization process?

Give scientific reason:Copper and brass utensils are tinned.

Distinguish between acid and alkali :Acid and Alkali.

Classify the following into acidic substances, basic substances and salts. (1) Lime water, (2) soda water, (3) soap water, (4) sea water, (5) sweet limeuice, (6) sugar caneuice, (7) buttermilk, (8) a mixture of ash in water, (9) tamarind water.

State true or false.(i) Oxides of metals are alkaline in nature.(ii) Salt is acidic.(iii) Metal corrodes due to salts.(iv) Salts are neutral.

Collect soil samples from your surroundings and find out whether it is acidic or alkaline or neutral?

Rewrite the following statement by selecting the correct option:The colour of phenolphthalein indicator in alkaline solution is …………. (a) yellow (b) green (c) orange (d) pink

Give scientific reason:Quicklime or slaked lime is added to the soil.

Find the odd one out and justify:Lime, litmus, phenolphthalein, methyl orange.

By squeezzing lemon on a piece of rock the gas liberated turned lime water milky. Which compound is present in the rock?

Match the pairs. Group AGroup B1. Tamarinda. Acetic acid2. Curdb. Citric acid3. Lemonc. Tartaric acid4. Vinegard. Lactic acid

A solution turns blue litmus red. Its pH is likely to be:A. 7B. 5C. 8D. 14

A solution turns phenolphthalein indicator pink. The most likely pH of this solution will be:A. 6B. 4C. 9D. 7

The colour of methyl orange indicator in a solution in yellow. The pH of this solution is likely to be:A. 7B. less than 7C. 0D. more than 7

Two drinks P and Q gave acidic and alkaline reactions, respectively one has a pH value of 9?

You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?

The pH of soil A is 7.5 while that of soil B is 4.5. Which of the two soils, A or B, should be treated powdered chalk to adjust its pH and why?

Name the indicator which can give us an idea of how strong or weak an acid or base is.

State the names of three weak alkalis.

Rewrite the following statement by selecting the correct options:When blue litmus paper is added to NaOH, the colour of the litmus paper will be ……………. . (a) blue (b) red (c) pink (d) yellow

State two acid-base indicators and mention their colour change.

Match the following:Column ‘A’Column ‘B’1. Sodium hydroxidea. Whitewashing2. Magnesium hydroxideb. Fertilizers3. Calcium hydroxidec. Washing soap4. Ammonium hydroxided. Antacid

(a). The pH values of six solutions A to F are given below: A=0, B=11, C=6, D=3, E=13, F=8 Which of the above solutions are (i) acids (ii) alkalis? (b). Name the acids or alkalis used to make (i) can batteries (ii) explosives (iii) soaps (iv) fertilisers.

A salt whose aqueous solution will hae a pH of more than 7 will be:A. `K_(2)CO_(3)`B. `K_(2)SO_(4)`C. `NaCl`D. `NH_(4)Cl`

Which of the following salts will give an aqueous solution having pH of almost 7?A. `NH_(4)NO_(3)`B. `NH_(4)Cl`C. `CaCl_(2)`D. `KCl`

One of the following salts will give an alkaline solution on dissolving in water. This is:A. `Na_(2)CO_(3)`B. `Na_(2)SO_(4)`C. `NaCl`D. `(NH_(4))_(2)SO_(4)`

The products of chlor-alkali process are:A. `NaCl,Cl_(2) and H_(2)`B. `H_(2),Cl_(2) and NaOH`C. `Cl_(2),Na_(2)CO_(3) and H_(2)O`D. `NaOH,Cl_(2) and HCl`

Two solutions A and B have pH values of 3.0 and 9.5 respectively. Which of these will turn litmus solution from blue to red and which will turn phenolphthalein from colourless to pink?

The aqueous solution of one of the following satls will turn red litmus to blue. This salt is:A. potassium sulphateB. sodium sulphatC. sodium chloirdeD. potassium carbonate

The salt whose aqueous solutio will turn blue litmus to red is:A. ammonium sulphateB. sodium acetateC. sodium chlorideD. potassium carbonate

The salt whose aqueous solution will have no effect on either red litmus or blue litmus isA. potassium sulphateB. sodium carbonateC. ammonium sulphateD. sodium acetate

Why does dry HCl gas not change the colour of the dry litmus paper?

10 mL of a solution of NaOH is found to be completely neutralised by 8 mL of a given solution of HCl. If we take 20 mL of the same solution of NaOH, the amount HCl solution (the same solution as before) required to neutralise it will beA. 4mLB. 8 mLC. 12 mLD. 16 mL

(a). What would you expect the pH of pure water to be? (b). What colour would the universal indicator show in an aqueous solution of sugar? Why? (c). A sample of rain water turned universal indicator paper yellow. What would you expect its pH to be? Is it a strong or a weak acid?

A beaker of concentrated hydrochloric acid has a pH of 1. What colour will full range universal indicator turn if it is added to this beaker? Is it a strong or a weak acid?

Five solutions A,B,C,D and E when tested with universal indicator showed pH as 4,1,11,7 and 9, respectively. Which solution is (a) neutral? (b) strongly alkaline? (c) strongly acidic? (d) weakly acidic? (e) weakly alkaline? Arrange the pH in increasing order of hydrogen-ion concentration.

Te pH values of five solutions, A, B,C,D and E are given below: A 1 B 5 C 7 D 11 E 13 ltbr. Which solution is (i) weakly alkaline (ii) neutral (iii) strongly acidic (iv) strongly alkaline, and (v) weakly acidic?

What colour will universal indicator show if you add it to the following substnaces? (a). Potassium hydroxide pH=12 (b). Soda water, pH=5 (c). Sulphuric acid, pH=2.