1. Differentiate between ore and mineral? (1)
2. Nitrogen is inert compared to phosphorous why? (1)
3. Give an example of shape selective catalyst? (1)
4. What are aerosols give example. (1)
5. Why do Zr and Hf exhibit similar properties ? (1)
6. Assign a reason (2)
a)Ammonia is stronger base than phosphine
b)Catenation tendency of Sulphur is more than Oxygen . Read more…
SUBJECT : CHEMISTRY CLASS – XII MAX. MARKS : 70 TIME : 3 HRS.
· Answer all questions.
· Questions 1 to 8 carry one mark each. Answer them in one word or sentence.
· Questions 9 to 18 are short answer questions and carry two marks each.
· Questions 19 to 27 are also short answer questions and carry three marks each.
· Questions 28 to 30 are long answer questions and carry 5 marks each.
1. What are the physical state of dispersed phase and dispersion medium of emulsion?
2. The formula of a compound is A2B3 with a hcp lattice. What fraction of tetrahedral voids are occupied?
3. What is the purpose of adding xanthates to sulphide ores?
4. What is the charge on the sol formed when KI is added to excess AgNO3?
Pentavalent Bismuth is a strong oxidizing agent. Why?
6. Write IUPAC name of
7. What is carbylamine reaction?
8. Both cellulose and starch are made up of glucose units. Starch can be digested by humans but cellulose cannot be digested. Why?
9. (i) What is the reason for abnormal molecular mass of solute?
(ii) A person suffering from high blood pressure should take less common salt. Why?
10. Give reason
a) 1 gm. of pulverized wood burns faster than 1 gm. of a piece of wood.
b) Reactions of higher molecularity are rare.
11. How will you distinguish between o/w and w/o emulsions? Read more…