FRANK Solutions for Class 10 Chemistry Chapter 9 - B - Nitric Acid

Chapter 9B - Nitric acid Exercise 235

Question 1

Solution 1

Question 2

Solution 2

Question 3

Solution 3

Chapter 9B - Nitric acid Exercise 236

Question 1

Solution 1

Question 2

Solution 2

Question 3

Solution 3

Question 4

Solution 4

Question 5

Solution 5

Question 6

Solution 6

Question 7

Solution 7

Question 8

Solution 8

Question 9

Solution 9

Question 10

Solution 10

Question 11

Solution 11

Question 12

Solution 12

Question 13

Solution 13

Question 14

Solution 14

Chapter 9B - Nitric acid Exercise 237

Question 1

Solution 1

Question 2

Solution 2

Question 3

Choose the correct answer from the options given below :

(i) Nitric acid on standing develops brownish colour which may be attributed to the presence of :

(ii) Concentrated nitric acid oxidises phosphorus to :

(a) H₃PO₄

(b) P₂O₃

(c) H₃PO₂

(d) H₄P₂O₇

(iii) When treated with nitric acid which of the following liberate hydrogen?

(a) Zinc

(b) Magnesium

(c) Copper

(d) Mercury

(iv) The catalyst used in the manufacture of HNO₃ by Ostwald process is

(a) Platinum black

(b) Finely dividend nickel

(c) Vanadium pentoxide

(d) Platinum gauze

Solution 3

(i) NO₂

(ii) H₃PO₄

(iii) Magnesium

(iv) Platinum gauze

Question 4

Fill in the blank with appropriate word/words

(i) Aqua regia is a mixture of _______ and________

(ii) Furning nitric acid is obtained by dissolving an excess of _______ in conc. Nitric acid

(iii) 98% nitric acid is obtained by distilling 68% nitric acid with ________ under ______

(iv) Ammonal is a mixture of ________ and __________

(v) 3 Cu + 8 HNO₃ (dilute) → _______ + 4H₂O + _________

Solution 4

(i) Aqua regia is a mixture of nitric acid and hydrochloric acid.

(ii) Fuming nitric acid is obtained by dissolving excess of nitrogen oxide in conc. nitric acid.

(iii) 98% nitric acid is obtained by distilling 68% nitric acid with conc. H₂SO₄ under pressure.

(iv) Ammonal is a mixture of ammonium nitrate and aluminium powder.

(v) 3Cu + 8HNO₃ (dilute) → 3Cu(NO₃)₂ + 4H₂O + 2NO

Question 5

Solution 5

Question 6

Solution 6

Question 7

Solution 7

Question 8

Solution 8

Question 9

Solution 9

Question 10

Solution 10

Chapter 9B - Nitric acid Exercise 238

Question 1

Solution 1

Question 2

Solution 2

Question 3

Solution 3

Question 4

Solution 4

Question 5

Solution 5

Question 6

Solution 6

Question 7

Solution 7

Question 8

Solution 8

Question 9

Describe what you see when concentrated nitric acid is added to copper.

Solution 9

When concentrated nitric acid is added to copper brown fumes of nitrogen dioxide are observed.

Question 10

Solution 10

Question 11

Name (formula is not acceptable) the gas produced in each of the following reactions:
(i)      By the action of concentrated nitric acid on copper.
(ii)     On warming ammonium sulphate with sodium hydroxide solution.

Solution 11

(i)          Nitrogen dioxide
(ii)         Ammonia gas

Question 12

Solution 12

Question 13

Solution 13

Question 14

Solution 14

Question 15

Solution 15

Chapter 9B - Nitric acid Exercise 239

Question 1

Solution 1

Question 2

Solution 2

Question 3

Solution 3

Question 4

Solution 4

Question 5

Solution 5

Question 6

Solution 6

Question 7

Solution 7

Question 8

Solution 8

Question 9

Solution 9

Chapter 9B - Nitric acid Exercise 240

Question 1

Solution 1

Question 2

Solution 2

Question 3

Solution 3

Question 4

(i) What is the special feature of the apparatus that is used in the laboratory preparation of nitric acid?

(ii) Why should the temperature of the reaction mixture of nitric acid not be allowed to rise above 200^oC?

Solution 4

(i) The complete apparatus should be made of glass only.

(ii) At high temperature, nitric acid decomposes and the glass apparatus may get damaged. Sodium formed at a higher temperature forms a hard crust which sticks to the walls of the retort. 

Question 5

What would you observe in the following case :

Copper is heated with concentrated nitric acid in a hard glass test rube.

Solution 5

Brown fumes of nitrogen dioxide are produced. Copper reacts with concentrated nitric acid to produce copper nitrate, water and nitrogen dioxide.

Question 6

(i) Identify the gas evolved when sulphur is treated with concentrated NH₃.

(ii) Balanced equation of oxidation of carbon with concentrated HNO₃

Solution 6

(i) When sulphur is treated with conc. nitric acid, it produces nitrogen dioxide.

(ii) 

Question 7

Explain the following :

(i) Dilute nitric acid is generally considered a typical acid but not so in its reaction with metals

(ii) Concentrated nitric acid appears yellow when it is left standing in a glass bottle.

(iii) An all glass apparatus is used in the laboratory preparation of nitric acid.

Solution 7

(i) Dilute nitric acid is generally considered a typical acid except for its reaction with metals because it does not liberate hydrogen. It is a powerful oxidising agent, and nascent oxygen formed oxidises hydrogen in water.

(ii) Although pure concentrated nitric acid is colourless, it appears yellow when left standing in a glass bottle due to the dissolution of reddish brown nitrogen dioxide gas in the acid. Nitrogen dioxide is produced because of the thermal decomposition of a portion of nitric acid.

 4HNO₃  → 2H₂O + 4NO₂ + O₂

(iii) An all-glass apparatus is used in the laboratory preparation of nitric acid because nitric acid vapour corrodes rubber and cork.

Question 8

Fill in the blanks using the appropriate words given below :

(Sulphur dioxide, Nitrogen dioxide, Nitric oxide, Sulphuric acid)

(i) Cold, dilute nitric acid reacts with copper to give ______.

(ii) Hot, concentrated nitric add reacts with sulphur to form ______.

Solution 8

(i) Cold, dilute nitric acid reacts with copper to give nitric oxide.

(ii) Hot, concentrated nitric acid reacts with sulphur to form nitrogen dioxide.

Question 9

Write a balanced equation for following :

(i) Action of cold and dilute nitric acid on copper

(ii) Action of conc. Nitric acid on sulphur

(iii) Reaction of ammonia with nitric acid

(iv) Laboratory preparation nitric acid.

Solution 9

(i) 3Cu + 8HNO₃→ 3Cu(NO₃)₂ + 4H₂O+ 2NO↑

(ii)   

(iii)   

(iv)