#### Model Paper 2

11th Standard

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Chemistry

Time : 00:50:00 Hrs
Total Marks : 80

Part-A

10 x 1 = 10
1. Which of the following statements about hydrogen is incorrect?

(a)

Hydrogen ion, H3O+ exists freely in solution.

(b)

Dihydrogen acts as a reducing agent.

(c)

Hydrogen has three isotopes of which tritium is the most common.

(d)

Hydrogen never acts. as cation in ionic salts

2. Water gas is

(a)

H2O(g)

(b)

CO + H2O

(c)

CO + H2

(d)

CO + N2

3. The cause of permanent hardness of water is due to

(a)

Ca(HCO3)2

(b)

Mg(HCO3)2

(c)

CaCl2

(d)

MgCO3

4. Zeolite used to soften hardness of water is hydrated

(a)

Sodium aluminium silicate

(b)

Calcium aluminium silicate

(c)

Zinc aluminium borate

(d)

Lithium aluminium hydride

5. A commercial sample of hydrogen peroxide marked as 100 volume H2O2, it means that

(a)

1 ml of H2O2 will give 100 ml O2 at STP

(b)

1 L of H2O2 will give 100 ml O2 at STP

(c)

1 L of H2O2 will give 22.4 L O2

(d)

1 ml of H2O2  will give 1 mole of O2 at STP

6. The reaction H3PO2 + D2O ➝ H2DPO2 + HDO indicates that hypo-phosphorus acid is

(a)

tribasic acid

(b)

dibasic acid

(c)

mono basic acid

(d)

none of these

7. In solid ice, oxygen atom is surrounded

(a)

tetrahedrally by 4 hydrogen atoms

(b)

octahedrally by 2 oxygen and 4 hydrogen atoms

(c)

tetrahedrally by 2 hydrogen and 2 oxygen atoms

(d)

octahedrally by 6 hydrogen atoms

8. Assertion: Permanent hardness of water is removed by treatment with washing soda.
Reason: Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates

(a)

Both assertion and reason are true and reason is the correct explanation of assertion.

(b)

Both assertion and reason are true but reason is not the correct explanation of assertion.

(c)

Assertion is true but reason is false

(d)

Both assertion and reason are false

9. Find the wrong statement

(a)

sodium metal is used in organic qualitative analysis

(b)

sodium carbonate is soluble in water and it is used in inorganic qualitative analysis

(c)

potassium carbonate can be prepared by solvay process

(d)

potassium bicarbonate is acidic salt

10. Lithium shows diagonal relationship with

(a)

sodium

(b)

magnesium

(c)

calcium

(d)

aluminium

11. Part-B

10 x 2 = 20
12. Write a note on Haber's process.

13. What is Hydrogenation?

14. What are the advantages of using hydrogen as fuel?

15. Complete the following reactions and balance them:
(i) CO(g)+H2(g)
(ii) CH4(g)+H2O(g) $\overset { 1270K }{ \underset { Ni }{ \rightarrow } }$

16. What happens when steam is passed over hot iron.

17. Explain the reaction of water with halogens.

18. What causes hardness in water?

19. What is Heavy water?

20. How is plaster of paris prepared?

21. Give the uses of gypsum

22. Part-C

10 x 5 = 50
23. Compare the structures of H2O and H2O2 .

24. Illustrate the industrial applications of hydrogen depending on
(i) The heat liberated when its atoms are made to combine on the surface of metal.
(ii) Its effect on unsaturated organic system.
(iii) Its ability to combine with nitrogen under specific conditions.

25. List out the uses of hydrogen.

26. Difference between ortho and para hydrogen

27. An element (A) belonging to group number 1 and period number 3 react with dihydrogen to form anhydride (B). The element (A) reacts with the universal solvent to give a strong base (C). Identify A, B, and C.

28. Identify the compound (A) which is a universal solvent. Compound A reacts with chlorine gas to give B and C. Compound A dissolves in an ionic compound of silicon to give compound D. Identify A and write the equations involved in the formation of B, C, and D.

29. Compound A is an important peroxide which disproportionates to give oxygen and water. Compound A reacts with ferrous sulphate under the acidic condition to give compound B. Compound A reacts with KMnO4 in basic condition to form (C) and (D) along with water and CO2 What are A, B, C and D? Write down the equations involved in their formation.

30. An element (A) which is used in metallurgy for the reduction of metal oxide to metal reacts with carbon monoxide and forms an industrial solvent (B). The industrially produced element (A) reacts with nitrogen to form compound (C). Identify A, B, and C.

31. Dihydrogen reacts with dioxygen (O2) to form water. Write the name and formula of the product when the isotope of hydrogen which has one proton and one neutron in its nucleus is treated with oxygen. Will the reactivity of both the isotopes be the same towards oxygen? Justify your answer.

32. When the first element of the periodic table is treated with dioxygen, it gives a compound whose solid state floats on its liquid state. This compound has an ability to act as an acid as well as a base. What products will be formed when this compound undergoes autoionisation?