Chapter - 2
Acids, Bases And Salts
āĻāĻিāĻĄ, āĻ্āώাā§°āĻ āĻā§°ু āĻ˛ā§ąāĻŖ
EXERCISES
āĻŦ্ā§াā§াāĻŽ
1. A solution turns red litmus blue, its pH is likely to be
ā§§) āĻāĻা āĻĻ্ā§°ā§ą ā§°āĻা āϞিāĻāĻŽাāĻ āύীāϞা āĻšৈ āĻĒā§°ে, āĻāϝ়াā§° pH āĻšোā§ąাā§° āϏāĻŽ্āĻাā§ąāύা āĻĨাāĻে
(a) 1 (b) 4 (c) 5 (d) 10
(āĻ) ā§§ (āĻ) ā§Ē (āĻ) ā§Ģ (āĻ) ā§§ā§Ļ
Answer:-
2. A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains
⧍) āĻāĻা āĻĻ্ā§°ā§ąāĻŖে āĻুāĻĄ়ি āĻāĻŖী-āĻোāϞাā§° āϏৈāϤে āĻŦিāĻ্ā§°িāϝ়া āĻā§°ি āĻāĻা āĻেāĻ āĻĻিāϝ়ে āϝিāϝ়ে āĻূāĻŖ-āĻĒাāύী āĻাāĻীā§°ā§° āĻĻā§°ে āĻā§°ি āϤোāϞে। āĻĻ্ā§°ā§ąāĻোāϤ āĻĨাāĻে
(a) NaCl (b) HCI (c) LiCl (d) KCI
Answer:-
3. 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 be
ā§Š) NaOH ā§° ā§§ā§Ļ āĻŽিāϞিāϞিāĻাā§° āĻĻ্ā§°ā§ąāĻŖ HCl ā§° ā§Ž āĻŽিāϞিāϞিāĻাā§° āĻĻ্ā§°ā§ąāĻŖেā§°ে āϏāĻŽ্āĻĒূā§°্āĻŖā§°ূāĻĒে āύিāώ্āĻ্ā§°িāϝ় āĻšোā§ąা āĻĻেāĻা āϝাāϝ়। āϝāĻĻি āĻāĻŽি NaOH ā§° āĻāĻেāĻা āĻĻ্ā§°ā§ąā§° ⧍ā§Ļ āĻŽিāϞিāϞিāĻাā§° āϞāĻঁ, āϤেāύ্āϤে āĻāϝ়াāĻ āύিāώ্āĻ্ā§°িāϝ় āĻā§°িāĻŦāϞৈ āĻĒ্ā§°āϝ়োāĻāύীāϝ় āĻĒā§°িāĻŽাāĻŖā§° HCl āĻĻ্ā§°ā§ą (āĻĒূā§°্āĻŦā§° āĻĻā§°ে āĻāĻেāĻা āĻĻ্ā§°ā§ąāĻŖ) āĻš’āĻŦ
(a) 4 mL (b) 8 mL (c) 12 mL (d) 16 mL
(āĻ) ā§Ē āĻŽিāϞিāϞিāĻাā§° (āĻ) ā§Ž āĻŽিāϞিāϞিāĻাā§° (āĻ) ⧧⧍ āĻŽিāϞিāϞিāĻাā§° (āĻ) ā§§ā§Ŧ āĻŽিāϞিāϞিāĻাā§°
Answer:-
4. Which one of the following types of medicines is used for treating indigestion?
ā§Ē/ āĻŦāĻĻāĻšāĻāĻŽ ā§°োāĻ āύিā§°াāĻŽāϝ়ā§° āĻŦাāĻŦে āϤāϞ⧰ āĻোāύāĻŦিāϧ āĻāώāϧ āĻŦ্āĻ¯ā§ąāĻšাā§° āĻā§°া āĻšāϝ়?
(a) Antibiotic (b) Analgesic (c) Antacid (d) Antiseptic
(āĻ) āĻāύ্āĻিāĻŦাāϝ়āĻিāĻ (āĻ) āĻŦিāώāύাāĻļāĻ (āĻ) āĻāύ্āĻাāĻিāĻĄ (āĻ) āĻāύ্āĻিāĻেāĻĒ্āĻিāĻ
Answer:-
5. Write word equations and then balanced equations for the reaction taking place when -
5. - āϤেāϤিāϝ়া āϏংāĻāĻিāϤ āĻšোā§ąা āĻŦিāĻ্ā§°িāϝ়াā§° āĻŦাāĻŦে āĻļāĻŦ্āĻĻ āϏāĻŽীāĻā§°āĻŖ āĻā§°ু āϤাā§° āĻĒিāĻāϤ āϏুāώāĻŽ āϏāĻŽীāĻā§°āĻŖ āϞিāĻা।
(a) dilute sulphuric acid reacts with zinc granules.
(āĻ) āĻĒাāϤāϞ āĻাāϞāĻĢিāĻā§°িāĻ āĻāĻিāĻĄে āĻিংāĻā§° āĻĻাāύাāĻŦোā§°ā§° āϏৈāϤে āĻŦিāĻ্ā§°িāϝ়া āĻā§°ে।
(b) dilute hydrochloric acid reacts with magnesium ribbon.
(āĻ) āĻĒাāϤāϞ āĻšাāĻāĻĄ্ā§°āĻ্āϞ⧰িāĻ āĻāĻিāĻĄে āĻŽেāĻāύেāĻিāϝ়াāĻŽ āĻĢিāϤাā§° āϏৈāϤে āĻŦিāĻ্ā§°িāϝ়া āĻā§°ে।
(c) dilute sulphuric acid reacts with aluminium powder.
(āĻ) āĻĒাāϤāϞ āĻাāϞāĻĢিāĻā§°িāĻ āĻāĻিāĻĄে āĻāϞুāĻŽিāύিāϝ়াāĻŽ āĻুāĻĄ়িā§° āϏৈāϤে āĻŦিāĻ্ā§°িāϝ়া āĻā§°ে।
(d) dilute hydrochloric acid reacts with iron filings.
(āĻ) āĻĒাāϤāϞ āĻšাāĻāĻĄ্ā§°āĻ্āϞ⧰িāĻ āĻāĻিāĻĄে āϞোā§° āĻĢাāĻāϞিāĻā§° āϏৈāϤে āĻŦিāĻ্ā§°িāϝ়া āĻā§°ে।
Answer:-
6. Compounds such as alcohols and glucose also contain hydrogen but are not categorised as acids. Describe an Activity to prove it.
ā§Ŧ) āĻāϞāĻāĻšāϞ āĻā§°ু āĻ্āϞুāĻ’āĻā§° āĻĻā§°ে āϝৌāĻāĻŦোā§°āϤো āĻšাāĻāĻĄ্ā§°’āĻেāύ āĻĨাāĻে āϝāĻĻিāĻ āĻāĻিāĻĄ āĻšিāĻাāĻĒে āĻļ্ā§°েāĻŖীāĻুāĻ্āϤ āύāĻšāϝ়। āĻāĻা āĻাā§°্āϝāĻāϞাāĻĒ āĻĒ্ā§°āĻŽাāĻŖ āĻā§°িāĻŦāϞৈ āĻŦā§°্āĻŖāύা āĻā§°া।
Answer:-
7. Why does distilled water not conduct electricity, whereas rain water does?
ā§/ āĻĄিāώ্āĻিāϞāĻĄ āĻĒাāύীāϝ়ে āĻŦিāĻĻ্āϝুā§ āĻĒā§°িāĻŦাāĻšী āύāĻā§°ে, āĻāύāĻšাāϤে āĻŦā§°āώুāĻŖā§° āĻĒাāύীāϝ়ে āĻিāϝ় āĻā§°ে?
Answer:-
8. Why do acids not show acidic behaviour in the absence of water?
ā§Ž) āĻĒাāύীā§° āĻ āύুāĻĒāϏ্āĻĨিāϤিāϤ āĻāĻিāĻĄāĻŦোā§°ে āĻিāϝ় āĻāĻিāĻĄিāĻ āĻāĻā§°āĻŖ āĻĻেāĻুā§ąাāĻŦ āύোā§ąাā§°ে?
Answer:-
9. 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
⧝) āĻāĻāύিāĻাā§°্āĻেāϞ āĻāύāĻĄিāĻেāĻā§°ā§° āϏৈāϤে āĻĒā§°ীāĻ্āώা āĻā§°িāϞে āĻĒাঁāĻāĻা āĻĻ্ā§°ā§ą A,B,C,D āĻā§°ু E āϝ়ে pH āĻ্ā§°āĻŽে ā§Ē,ā§§,ā§§ā§§,ā§ āĻā§°ু ⧝ āĻĻেāĻুā§ąাāĻāĻিāϞ। āĻোāύāĻো āϏāĻŽাāϧাāύ
(a) neutral?
(āĻ) āύিā§°āĻĒেāĻ্āώ?
(b) strongly alkaline?
(āĻ) āĻĒ্ā§°āĻŦāϞāĻাā§ąে āĻ্āώাā§°āĻীāϝ়?
(c) strongly acidic?
(āĻ) āĻĒ্ā§°āĻŦāϞāĻাā§ąে āĻ āĻŽ্āϞীāϝ়?
(d) weakly acidic?
(āĻ) āĻĻুā§°্āĻŦāϞāĻাā§ąে āĻ āĻŽ্āϞীāϝ়?
(e) weakly alkaline?
(āĻ) āĻĻুā§°্āĻŦāϞāĻাā§ąে āĻ্āώাā§°āĻীāϝ়?
Arrange the pH in increasing order of hydrogen-ion concentration.
āĻšাāĻāĻĄ্ā§°āĻেāύ-āĻāϝ়āύ⧰ āĻāύāϤ্āĻŦā§° āĻŦৃāĻĻ্āϧি āĻĒোā§ąা āĻ্ā§°āĻŽāϤ pH āϏāĻাāĻāĻ।
Answer:-
10. Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCI) is added to test tube A, while acetic acid (CH3COOH) is added to test tube B. Amount and concentration taken for both the acids are same. In which test tube will the fizzing occur more vigorously and why?
ā§§ā§Ļ) āĻĒā§°ীāĻ্āώা āύāϞী A āĻā§°ু B āϤ āϏāĻŽাāύ āĻĻৈā§°্āĻ্āϝ⧰ āĻŽেāĻāύেāĻিāϝ়াāĻŽ āĻĢিāϤা āϞোā§ąা āĻšāϝ়।āĻĒā§°ীāĻ্āώা āύāϞী A āϤ āĻšাāĻāĻĄ্ā§°āĻ্āϞ⧰িāĻ āĻāĻিāĻĄ (HCI) āϝোāĻ āĻā§°া āĻšāϝ়, āĻāύāĻšাāϤে āĻĒā§°ীāĻ্āώা āύāϞী B āϤ āĻāĻিāĻিāĻ āĻāĻিāĻĄ (CH3COOH) āϝোāĻ āĻā§°া āĻšāϝ়।āĻĻুāϝ়োāĻা āĻāĻিāĻĄā§° āĻŦাāĻŦে āϞোā§ąা āĻĒā§°িāĻŽাāĻŖ āĻā§°ু āĻāύāϤ্āĻŦ āĻā§°া āĻšāϝ় āĻāĻেāĻ. āĻোāύāĻো āĻেāώ্āĻ āĻিāĻāĻŦāϤ āĻĢিāĻিং āĻ āϧিāĻ āĻোā§°েā§°ে āĻš’āĻŦ āĻā§°ু āĻিāϝ়?
Answer:-
11. Fresh milk has a pH of 6. How do you think the pH will change as it turns into curd? Explain your answer.
ā§§ā§§) āϏāϤেāĻ āĻাāĻীā§°ā§° pH ā§Ŧ āĻšāϝ়, āĻĻৈāϞৈ āĻĒā§°িāĻŖāϤ āĻšোā§ąাā§° āϞāĻে āϞāĻে pH āĻেāύেāĻৈ āϏāϞāύি āĻš’āĻŦ āĻŦুāϞি āĻāĻĒুāύি āĻাāĻŦে? āĻāĻĒোāύাā§° āĻāϤ্āϤ⧰āĻো āĻŦুāĻাāĻ āĻĻিāϝ়āĻ।
Answer:-
12. A milkman adds a very small amount of baking soda to fresh milk.
⧧⧍) āϏāϤেāĻ āĻাāĻীā§°āϤ āĻāĻāύ āĻাāĻীā§° āĻĻিāϝ়া āĻŽাāύুāĻšে āĻ āϤি āĻāĻŽ āĻĒā§°িāĻŽাāĻŖā§° āĻŦেāĻিং āĻ’āĻĄা āĻŽিāĻšāϞাāĻ āĻĻিāϝ়ে।
(a) Why does he shift the pH of the fresh milk from 6 to slightly alkaline?
(āĻ) āϤেāĻঁ āϏāϤেāĻ āĻাāĻীā§°ā§° pH ā§Ŧā§° āĻĒā§°া āĻ āϞāĻĒ āĻ্āώাā§°āĻীāϝ়āϞৈ āĻিāϝ় āϏ্āĻĨাāύাāύ্āϤ⧰িāϤ āĻā§°ে?
(b) Why does this milk take a long time to set as curd?
(āĻ) āĻāĻ āĻাāĻীā§°āĻ āĻĻৈ āĻšিāĻাāĻĒে āϏ্āĻĨাāĻĒāύ āĻā§°িāĻŦāϞৈ āĻিāϝ় āĻŦāĻšু āϏāĻŽāϝ় āϞাāĻে?
Answer:-
13. Plaster of Paris should be stored in a moisture-proof container. Explain why?
ā§§ā§Š) āĻĒেā§°িāĻā§° āĻĒ্āϞাāώ্āĻাā§° āĻā§°্āĻĻ্ā§°āϤা āύāĻĨāĻা āĻĒাāϤ্ā§°āϤ ā§°াāĻিāĻŦ āϞাāĻে। āĻিāϝ় āĻŦুāĻাāĻ āĻĻিāϝ়āĻ?
Answer:-
14. What is a neutralisation reaction? Give two examples.
ā§§ā§Ē) āύিāώ্āĻ্ā§°িāϝ়āĻā§°āĻŖ āĻŦিāĻ্ā§°িāϝ়া āĻি? āĻĻুāĻা āĻāĻĻাāĻšā§°āĻŖ āĻĻিāϝ়া।
Answer:-
15. Give two important uses of washing soda and baking soda.
ā§§ā§Ģ) ā§ąাāĻļ্āĻŦিং āĻ’āĻĄা āĻā§°ু āĻŦেāĻিং āĻ’āĻĄাā§° āĻĻুāĻা āĻুā§°ুāϤ্āĻŦāĻĒূā§°্āĻŖ āĻŦ্āĻ¯ā§ąāĻšাā§° āĻĻিāϝ়āĻ।
Answer:-
Type by - Pinku Moni bora.
Post ID: DABP001679