#### Model question paper - II

11th Standard

Reg.No. :
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Chemistry

Time : 02:00:00 Hrs
Total Marks : 100

Part - A

30 x 1 = 30
1. 40 ml of methane is completely burnt using 80 ml of oxygen at room temperature The volume of gas left. after cooling to room temperature is

(a)

40 ml CO2 gas

(b)

40 ml CO2 gas and 80 ml H2O gas

(c)

60 ml CO2 gas and 60 ml H2O gas

(d)

120 ml CO2 gas

2. Fe2 + $\longrightarrow$ Fe3+ + e- is a ________ reaction.

(a)

redox

(b)

reduction

(c)

oxidation

(d)

decomposition

3. Which one of the following represents 180g of water?

(a)

5 Moles of water

(b)

90 moles of water

(c)

$\frac { 6.022\times { 10 }^{ 23 } }{ 180 }$ molecules of water

(d)

6.022 x 1024molecules of water

4. Among the three metals, zinc, copper and silver, the electron releasing tendency decreases in the following order.

(a)

zinc >silver >copper

(b)

zinc >copper >silver

(c)

silver > copper >zinc

(d)

copper > silver > zinc

5. Which of the following statement(s) is/are not true about the following decomposition reaction.
2KClO3 $\longrightarrow$ 2KCl + 3O2
(i) Potassium is undergoing oxidation
(ii) Chlorine is undergoing oxidation
(iii) Oxygen is reduced
(iv) None of the species are undergoing oxidation and reduction.

(a)

only (iv)

(b)

(i) and (iv)

(c)

(iv) and (iii)

(d)

All of these

6. Match the list-I with list-II and select the correct answer using the code given below the lists.

 List-I List-II A Cr2O72- 1 +5 B MnO4- 2 +6 C VO3- 3 +3 D FeF63+ 4 +7
(a)
 A B C D 3 1 4 2
(b)
 A B C D 4 3 2 1
(c)
 A B C D 2 4 1 3
(d)
 A B C D 3 2 1 4
7. Match the items in column list-I with relevant items in list-II.

 List-I List-II A Ions having positive charge 1 anion B Ions having negative charge 2 -1 C Oxidation number of fluorine in NaF 3 0 D The sum of oxidation number of all atoms in a neutral molecule 4 cation
(a)
 A B C D 3 4 2 1
(b)
 A B C D 1 2 3 4
(c)
 A B C D 2 3 4 1
(d)
 A B C D 4 1 2 3
8. The equivalent mass of ferrous oxalate is __________.

(a)

$\frac { molar\ mass\ of\ ferrousoxalate }{ 1 }$

(b)

$\frac { molar\ mass\ of\ ferrousoxalate }{ 2 }$

(c)

$\frac { molar\ mass\ of\ ferrousoxalate }{ 3 }$

(d)

None of these

9. Which of the following compound(s) has /have a percentage of carbon same as that in ethylene (C2H4)

(a)

propene

(b)

ethyne

(c)

benzene

(d)

ethane

10. Identify the correct statements with reference to the given reaction
P4 + 3OH- + 3H2O $\longrightarrow$ PH3 + 3H2PO2-
(i) Phosphorous is undergoing reduction only
(ii) Phosphorous is undergoing oxidation only
(iii) Phosphorous is undergoing both oxidation and reduction.
(iv) Hydrogen is undergoing neither oxidation nor reduction.

(a)

only (iii)

(b)

both (iii) and (iv)

(c)

only (i)

(d)

None of these

11. Identify the redox reaction taking place in a beaker.

(a)

Zn(s)+ Cu2+(aq) $\longrightarrow$ Zn2+(aq) + Cu(s)

(b)

Cu(s) + 2Ag+(aq) $\longrightarrow$ Cu2+(aq) + 2Ag(s)

(c)

Cu(s) + Zn2+(aq) $\longrightarrow$ Zn(s) + cu2+ (aq)

(d)

2Ag(s) + cu2+(aq) $\longrightarrow$ 2Ag+aq + Cu(s)

12. The solid state of matter is converted into gas by

(a)

sublimation

(b)

deposition

(c)

freezing

(d)

condensation

13. Match list I with list II and identify the correct code.

List I List II
A Bronze 1 Element
B Table Salt 2 Homogeneous mixture
C Gold 3 Alloy
D Petrol 4 Compound
(a)
 A B C D 1 4 2 3
(b)
 A B C D 3 4 1 2
(c)
 A B C D 2 3 4 1
(d)
 A B C D 4 2 3 1
14. Statement I: an Equivalent mass of Mg is  determined by Oxide Method
Statement II: Molecular mass is calculated using vapour density

(a)

Both the statements are individually true

(b)

Both the statements are individually true and statement II is the correct explanation of statement 1.

(c)

Statement I is true but statement IIis false.

(d)

Statement Iis false but statement IIis true

15. The volume occupied by any gas at S.T.P. is_____

(a)

22.4litres

(b)

2.24litres

(c)

224 litres

(d)

0.224 litres

16. One 'U' stands for the mass of

(a)

An atom of carbon-12

(b)

1/12th of the carbon-12

(c)

1/12th of a hydrogen atom

(d)

One atom of any of the element

17. What will be the basicity of H3BO3, which is not a protic acid?

(a)

One

(b)

Two

(c)

Three

(d)

Four

18. Calculate the percentage of N in ammonia molecule.

(a)

121.42%

(b)

28.35%

(c)

82.35%

(d)

28.53%

19. Assertion: The ash produced by burning paper in air is lighter than the original mass of paper.
Reason: he residue left after combustion of a chemical entity is always lighter

(a)

Both assertion and reason are correct and reason is the correct explanation for assertion.

(b)

Both assertion and reason are correct but reason is not the correct explanation for assertion

(c)

Assertion is true but reason are false

(d)

Both assertion and reason are false

20. Two electrons occupying the same orbital are distinguished by

(a)

azimuthal quantum number

(b)

spin quantum number

(c)

magnetic quantum number

(d)

orbital quantum number

21. Electron density in the yz plane of 3dxy-y2 orbital is

(a)

zero

(b)

0.50

(c)

0.75

(d)

0.90

22. Which of the following does not represent the mathematical expression for the Heisenberg uncertainty principle?

(a)

$\triangle x.\triangle p\ge \frac { h }{ 4\pi }$

(b)

$\triangle x.\triangle v\ge \frac { h }{ 4\pi m }$

(c)

$\triangle E.\triangle t\ge \frac { h }{ 4\pi }$

(d)

$\triangle E.\triangle x\ge \frac { h }{ 4\pi }$

23. Electronic configuration of species M2+ is 1s2 2s2 2p6 3s2 3p6 3d6 and its atomic weight is 56. The number of neutrons in the nucleus of species M is:

(a)

26

(b)

22

(c)

30

(d)

24

24. In which of the following options the order of arrangement does not agree with the variation of property indicated against it?

(a)

I< Br < CI < F (increasing electron gain enthalpy)

(b)

Li < Na < K < Rb (increasing metallic radius)

(c)

Al3+< Mg2+ < Na+ - (increasing ionic size)

(d)

B < C < O < N (increasing first ionisation enthalpy)

25. Which of the following elements will have the highest electro negativity

(a)

Chlorine

(b)

Nitrogen

(c)

Cesium

(d)

Fluorine

26. In the third period the first ionization potential is of the order.

(a)

Na > Al > Mg > Si > P

(b)

Na < Al < Mg < Si < P

(c)

Mg > Na > Si > P > Al

(d)

Na< Al < Mg < Si < P

27. Identify the wrong statement.

(a)

Amongst the isoelectronic species, smaller the positive charge on cation, smaller is the ionic radius

(b)

Amongst isoelectric species greater the negative charge on the anion, larger is the ionic radius

(c)

Atomic radius of the elements increases as one moves down the first group of the periodic table

(d)

Atomic radius of the elements decreases as one moves across from left to right in the 2nd period of the periodic table.

28. The element with positive electron gain enthalpy is

(a)

Hydrogen

(b)

Sodium

(c)

Argon

(d)

Fluorine

29. In a given shell the order of screening effect is

(a)

s > p > d > f

(b)

s > p > f > d

(c)

f > d > p > s

(d)

f > p > s > d

30. Which of the following orders of ionic radii is correct?

(a)

H- > H+ > H

(b)

Na+ > F- > O2-

(c)

F > O2- > Na+

(d)

None of these

31. Part - B

10 x 2 = 20
32. Calculate the molar mass of the following compounds. -boric Acid [H3BO3]

33. Balance the following equations by ion electron method - ${ C }_{ 2 }{ O }_{ 4 }^{ 2- }+{ Cr }_{ 2 }{ O }_{ 7 }^{ 2- }\longrightarrow { Cr }^{ 3+ }+{ CO }_{ 2 }$ (in acid medium)

34. Balance the following equations by ion electron method $Zn+{ NO }_{ 3 }^{ - }\longrightarrow { Zn }^{ 2+ }+No$

35. Balance the following equations by oxidation number method - $Cu+{ HNO }_{ 3 }\longrightarrow Cu\left( { No }_{ 3 } \right) _{ 2 }+{ No }_{ 2 }+{ H }_{ 2 }O$

36. Distinguish between a homogeneous and heterogeneous mixture.

37. Why atomic masses are called as relative atomic masses?

38. Define relative atomic mass

39. Calculate the equivalent masses of the following - HCl

40. 3 grams of hydrogen reacts with 29 g of O, to yield H2O. Which is the limiting reagent?

41. What do you understand by the terms acidity and basicity?

42. Calculate the screening constant in Zinc for (i) 4s electron, (ii) for a 3d electron. The electronic configuration of Zinc (30) is (ls)2 (2s, 2p)(3s,3p)8 (3d10) (4s)2

43. The element with atomic number 120 has not been discovered so far. What would be the IUPAC name and the symbol for this element? Predict the possible electronic configuration of this element.

44. The electron gain enthalpy of chlorine is 348 kJ mol-1. How much energy in kJ is released when 17.5 g of chlorine is completely converted into Cl- ions in the gaseous state?

45. Part - C

10 x 3 = 30
46. Which one of the two, ClO2- or ClO4- shows disproportionation reaction and why?

47. Calculate the empirical and molecular formula of a compound containing 76.6% carbon, 6.38 % hydrogen and rest oxygen its vapour density is 47

48. Calculate the amount of water produced by the combustion of 32 g of methane.

49. How many moles of hydrogen is required to produce 10 moles of ammonia?

50. How much volume of carbon dioxide is produced when 50 g of calcium carbonate is heated completely under standard conditions?

51. How much volume of chlorine is required to form 11.2 L of HCI at 273 K and 1 atm pressure?

52. Describe the Autbau principle

53. Show that the circumference of the Bohr orbit for the hydrogen atom is an integral multiple of the de Broglie wave length associated with the electron revolving arround the nucleus.

54. Calculate the uncertainty in position of an electron, if Av = 0.1% and $\upsilon$ = 2.2 x 106 ms-1.

55. Determine the values of all the four quantum numbers of the 8th electron in O- atom and 15th electron in CI atom and the last electron in chromium.

56. The electronic configuration of atom is one of the important factor which affects the value of ionisation potential and electron gain enthalpy. Explain.

57. In what period and group will an element with Z = 118 will be present?

58. Elements a, b, c and d have the following electronic configurations:
a: 1s2, 2s2, 2p6
b: 1s2, 2s2, 2p6, 3s2, 3p1
c: 1s2, 2s2, 2p6, 3s2, 3p6
d: 1s2, 2s2, 2p1
Which elements among these will belong to the same group of periodic table.

59. Part - D

Answer any 4 of the following questions

4 x 5 = 20
60. Calculate the molar mass of the following compounds. -
i) urea [CO(NH2)2]
ii) acetone [CH3 COCH3]
iii) boric Acid [H3BO3]
iv) Sulphurci  Acid [H2SO4]

61. A Compound on analysis gave Na = 14.31% S = 9.97% H= 6.22% and 0= 69.5% calculate the molecular formula of the compound if all the hydrogen in the compound is present in combination with oxygen as a water of crystallization. (molecular mass of the compound is 322).

62. Balance the following equations by ion electron method -
i) ${ KMn }O_{ 4 }+{ SnCl }_{ 2 }+HCI\longrightarrow MnCI_{ 2 }+{ SnCI }_{ 4 }+{ H }_{ 2 }O+KCI$
ii) ${ C }_{ 2 }{ O }_{ 4 }^{ 2- }+{ Cr }_{ 2 }{ O }_{ 7 }^{ 2- }\longrightarrow { Cr }^{ 3+ }+{ CO }_{ 2 }$ (in acid medium)
iii) ${ Na }_{ 2 }{ S }_{ 2 }{ O }_{ 3 }+{ I }_{ 2 }\longrightarrow { Na }_{ 2 }{ S }_{ 4 }{ O }_{ 6 }+NaI$
iv) $Zn+{ NO }_{ 3 }^{ - }\longrightarrow { Zn }^{ 2+ }+No$

63. Balance the following equations by oxidation number method.
CuO + NH3 ⟶ Cu +N2 + H2O

64. Balance the following equations by oxidation number method.
K2Cr2O7 + HI ⟶ KI + Crl3 + H2O + I2

65. What is screening effect? Briefly give the basis for pauling's scale of electronegativity.