Orgnisation : Council For Indian School Certificate Examinations
Exam : ISC (Class XII) Chemistry Practical
Document type : Question Paper
Website : cisce.org
Download Sample/Model Question Papers :
2014 : https://www.pdfquestion.in/uploads/cisce.org/5923-CHEMISTRY-PAPER-2-I-OF-II.pdf
2015 : https://www.pdfquestion.in/uploads/cisce.org/5923-Chemistry-Paper2-2-of-5.pdf
CISCE Chemistry Practical Question Paper
CHEMISTRY PAPER – 2 (PRACTICAL)
(Three hours)
Related / Similar Question Paper :
CISCE ISC Class XII Chemistry Theory Question Paper
(Candidates are allowed additional 15 minutes for only reading the paper. They must OT start writing during this time.) ALL ANSWERS MUST BE Written THE ANSWER BOOKLET PROVIDED SEPARATELY.
Question 1
You are provided with two solutions as follows :
** C-10 is a solution prepared by dissolving 1.04 gms of potassium manganate (VII) KMnO4 per litre.
** C-11 is a solution prepared by dissolving 13.4 gms of hydrated ammonium iron (II) sulphate crystals, (NH4)2SO4.FeSO4.xH2O per litre.
Procedure :
Rinse and fill the burette with the solution C-10 (KMnO4). Pipette out 20 ml or 25 ml of C-11 (hydrated ammonium iron (II) sulphate) into a clean conical flask. To this, add 20ml of dilute sulphuric acid C-12, specially provided for titration.
Titrate the solution with C-10 (KMnO4) till one drop of this gives a light permanent pink colour to the solution in the conical flask. Ensure that the pink colour does not disappear on shaking the contents of the conical flask. Repeat the experiment to get at least two concordant readings. Tabulate your readings.
State :
(a) The capacity of the pipette used.
(b) The titre value you intend to use in your calculations.
Show the titre value to the Visiting Examiner :
The equations for the above reactions are as follows
2KMnO4 + 3H2SO4 → K2SO4 + 2MnSO4 + 3H2O + 5[O] 10(NH4)2SO4.FeSO4.xH2O+5H2SO4 + 5[O] → 10(NH4)2SO4 + 5Fe3(SO4)3+ 10 xH2O + 5H2O
Relative atomic masses :
K = 39 Fe = 56 S = 32 N = 14 H = 1 Mn = 55 O = 16
Calculate the following :
(i) The molarity* of potassium manganate (VII) solution C-10.
(ii) The molarity* of hydrated ammonium iron (II) sulphate solution C-11.
(iii) The molecular mass of hydrated ammonium iron (II) sulphate deduced from the experimental data.
(iv) The numerical value of x.
Note : Molarity must be calculated upto at least 4 decimal places.
Question 2
Substances C-13 and C-14 are organic compounds. Carry out the following experiments and note all the changes taking place at each step of the experiments.
Note the smell of the substance formed, colour of the substance obtained, colour of the precipitate formed, and solubility in excess of the reagent and any other observations you may have. State the identity of each compound on the basis of the experiments and observational changes.
Procedure :
(a) Substance C-13 :
1. Take 3 – 4 drops of C-13 in a test tube, add about 0.5 grams of potassium hydrogen sulphate and heat strongly.
2. Take 0.2 grams of borax in a test tube and add 5 ml of water to it. Shake well to get a clear solution. To this, add 2 drops of phenolphthalein solution. Now add 2- 3 drops of C-13 to this, shake well, warm and cool.
3. Take about 4 – 5 drops of C-13 in a test tube. Add about 1 ml of copper sulphate solution followed by a few drops of Sodium Hydroxide solution.
(b) Substance C-14 :
1. Take 2 ml freshly prepared Sodium nitroprusside aqueous solution. To this, add 2 ml of C-14 followed by Sodium Hydroxide solution drop by drop, and warm.
2. Take 2 ml of C-14 and to this add 2 ml of saturated Sodium Bisulphite solution. Shake.
3. Take 1 ml of C-14. To this, add 2 ml of Iodine solution followed by 10% Sodium Hydroxide solution. Warm on a water bath and cool.
4. Take 2 ml of C-14 in a test tube, add 1 ml of Mercuric chloride solution. Now, add Sodium Hydroxide solution drop-wise and shake.
Question 3
Analyse qualitatively the substance C-15 which contains two anions and two cations. Identify these ions.
(a) While testing for anions you must mention :
(i) How the solution/soda extract was prepared.
(ii) How the gases were identified.
(iii) The confirmatory test for anions. Show the results as required to the Visiting Examiner.
(b) While testing for cations you must mention :
(i) How the original solution for group analysis was prepared.
(ii) The formal group analysis with pertinent group reagents.
(iii) The confirmatory test for each cation.
Show the results as required to the Visiting Examiner.
Note : Use of qualitative analysis booklet/table is not allowed.
Question 4
Show the following to the Visiting Examiner for assessment :
(a) Project [7]
(b) Chemistry Practical File. [3]
Note : Question 2 will be set from any one OR a combination of any two of the following:
** Rate of Reaction
** Identification of Organic Compounds
** pH determination
** Test for carbohydrates and proteins.
View Comments (4)
What is the correct titre value in today practical?
What will be the probable value of titration in ISC 2017 chemistry practical paper?
How much did you get?
I had recently given my ISC 12th chemistry practical paper and I have question to ask. If in my paper I had find correct salt but by mistake I had written the experiment wrong then who much I should expect to get out off 4 marks. I request please to answer my question. It will be a great relief for me .