12th Chemistry All Activities

12th Chemistry Activity No. 1

    ~To prepare phthalic anhydride

MCQ

1.Phthalic acid is ______

Ans. b) dicarboxylic acid

2.Phthalic anhydride is obtained by the process known as _____

Ans. c) sublimation

3.Phthalic acid undergoes ______ during preparation of phthalic anhydride.

Ans. a) dehydration

4.Shape of crystals of phthalic anhydride is _____

Ans. a) needle 

5.Formation of phthalic anhydride takes place by ______ process/reaction

Ans. b) cyclisation

Short Answer Question

1. Why cotton plug is used in the process of sublimation?

Ans. The cotton plug slows down the rise of the warm gases and prevents their escape during sublimation so that they get more time to get condensed

2.Write chemical equation for preparation of acetic anhydride from acetic acid

Ans. 

3.What is the colour and shape of phthalic anhydride crystals?

Ans. A colourless solid with needle shape crystals.

4.Why slow heating is required to the contents during process of sublimation?

Ans. On slow heating, water molecule can get out from phthalic acid to form phthalic anhydride.

Click Here For PDF: Google Drive

12th Chemistry Activity No. 5

    ~Identify Resin Identification Code (RIC) / Recycle Symbols of plastics on different plastic materials.

MCQ

1.The following symbol indicate

Ans. a) universal recycling

2.The RIC code on cafeteria tray is ______

Ans. d) 6

3.If RIC code on plastic material is 7 then which type of material will be there

Ans. a) polylactic acid

4.The RIC on auto vehicle part is ______

Ans. c) 5

5.The code used for recycle symbols on different plastic material is ______

Ans. a) RIC

Short Answer Questions

1. What it indicates if there is no ♻️ such symbol on plastic material?

Ans. If plastic material have no such symbol then that plastic material is not recyclable.

2. Write RIC for beverage bottles?

Ans. RIC 1 is on beverage bottles.

3. ♻️5 signifies which type of plastic material?

Ans. ♻️5 signifies Polypropylene (PP) material.

4. Write RIC for food containers.

Ans. RIC ♻️5 is for food containers.

5. What was the purpose for development of RIC in 1988?

Ans. RIC was developed in 1988 to be able to sort and recycle plastic more efficiently by workers in plastic industry.

Click Here For PDF: Google Drive

12th Chemistry Activity No. 6

    ~To prepare 100 mL of 0.1 M standard solution of ferrous ammonium sulphate (Mohr's salt)

MCQ

1.The molar mass of F.A.S. is ________

Ans. b) 392 g/mol

2.To prepare standard 1M solution of F.A.S. _________

Ans. 

3.The second name of ferrous ammonium sulphate (F.A.S.) is __________

Ans. b) Mohr's salt

4.To prepare 100mL of standard 0.1M solution of F.A.S. ________

Ans. b) 3.92g of F.A.S.is dissolved in distilled water and diluted to 100cm3

5.The green colour of 0.1M F.A.S. solution turns to which colour if we keep the solution open in an air for long time?

Ans. c) yellowish brown

Short Answer Questions

1. Calculate the amount of F.A.S. required to prepare 1000mL of 0.1M standard solution of F.A.S.

Ans. 1000mL of 1M of F.A.S. solution contain 392g/mol

thus for 1000mL of 0.1M of F.A.S. solution should contain,

(1000 X 0.1 X 392) / (1000 X 1)

= 39.2g/mol

2. Calculate the molar mass of F.A.S. (Fe=56, S=32, N=14, O=16, h=1)

Ans. F.A.S. = Fe(SO4)2 . (NH4)2 . SO4 . 6H2O

= (56+32+64) + 2(14+4) + (32+64) + 6(2+16)

=392 g/mol

3.Why rhe 0.1 M F.A.S. solution becomes yellowish brown on keeping open for long time?

Ans. F.A.S. salt contain iron(2) which on exposing to ai, oxidizes and it forms iron(3) salt which gives yellowish brown colour.

4.Why it is necessary to add few drops of conc. H2SO4 in the preparation of F.A.S. solution?

Ans. If H2SO4 is added, the hydrolytic equilibrium shifts to left. Turbidity of Cu(OH)2 dissolves to give clear solution.

5.How many water of crystallisation are present in Mohr's salt?

Ans. 6

Click Here For PDF: Google Drive