#### 11th Standard Chemistry English Medium Free Online Test 1 Mark Questions 2020

11th Standard

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Chemistry

Time : 00:25:00 Hrs
Total Marks : 25

25 x 1 = 25
1. Total number of electrons present in 1.7 g of ammonia is

(a)

6.022 x 1023

(b)

$\frac { 6.022\times { 10 }^{ 22 } }{ 1.7 } \quad$

(c)

$\frac { 6.022\times { 10 }^{ 24 } }{ 1.7 }$

(d)

$\frac { 6.022\times { 10 }^{ 23 } }{ 1.7 }$

2. Identify the correct statement(s) with respect to the following reaction :
Zn + 2HCl $\longrightarrow$ ZnCl2 + H2
(i) Zinc is acting as an oxidant
(ii) Chlorine is acting as a reductant
(iii) Hydrogen is not acting as an oxidant
(iv) Zn is acting as a reductant

(a)

only (ii)

(b)

only (iv)

(c)

both (ii) and (iii)

(d)

both (ii) and (i)

3. Which one of the following is the standard for atomic mass?

(a)

1H1

(b)

6C12

(c)

6C14

(d)

8O16

4. How many grams are contained in 1 gram atom of Na?

(a)

13g

(b)

1 g

(c)

23 g

(d)

1/23g

5. When methane is burnt in oxygen to produce CO2 and H2O, the oxidation number of carbon changes by _______________.

(a)

-8

(b)

+4

(c)

Zero

(d)

+8

6. For d-electron, the orbital angular momentum is

(a)

$\frac { \sqrt { 2 } h }{ 2\pi }$

(b)

$\\ \frac { \sqrt { 2h } }{ 2\pi }$

(c)

$\frac { \sqrt { 2\times 4 } h }{ 2\pi }$

(d)

$\frac { \sqrt { 2\times 4 } h }{ 2\pi }$

7. Time independent Schnodinger wave equation is

(a)

$\overset { \wedge }{ H } \psi =E\psi$

(b)

${ \triangledown }^{ 2 }\psi +\frac { 8{ \pi }^{ 2 }m }{ { h }^{ 2 } } (E+V)\psi =0$

(c)

$\frac { { \partial }^{ 2 }\psi }{ { \partial x }^{ 2 } } +\frac { { \partial }^{ 2 }\psi }{ { \partial y }^{ 2 } } +\frac { { \partial }^{ 2 }\psi }{ { \partial z }^{ 2 } } +\frac { { 2m } }{ { h }^{ 2 } } (E-V)\Psi =0$

(d)

All of these

8. Consider the following statements regarding Rutherford's $\alpha$-ray scattering experiment.
i. Most of the $\alpha$-particles were deflected through a small angle.
ii. Some of $\alpha$-particles passed through the foil.
iii. Very few $\alpha$-particles were reflected back by 180o.
Which of the above statements is/are not correct.

(a)

i and ii

(b)

ii and iii

(c)

i and iii

(d)

i, ii and iii

9. Which of the following is the actual configuration of Cr (Z = 24)?

(a)

1s2 2s2 2p6 3s2 3p6 3d4 4s2

(b)

1s2 2s2 2p6 3s2 3p6 3d5 4s1

(c)

1s2 2s2 2p6 3s2 3p6 3d6

(d)

1s2 2s2 2p6 3s2 3p6 3d5 4s3

10. Assertion(A): Cr with electronic configuration [Ar] 3d5 4s1 is more stable than [Ar] 3d4 4s2.
Reason(R): Half filled orbitals have been found to have extra stability than partially filled orbitals.

(a)

A and R are correct and R is the correct explanation of A.

(b)

A and R are correct but R is not the correct the explanation of A.

(c)

A is correct but R is wrong.

(d)

A is wrong but R is correct.

11. Across the period, Ionisation energy _______

(a)

increases

(b)

decreases

(c)

does not vary

(d)

first decreases and then increases

12. Which of the following processes involves absorption of energy?

(a)

Cl(g) +e- ⟶ Cl-

(b)

O-(g) +e- ⟶ O2-

(c)

O(g) +e- ⟶ O(g)-

(d)

S(g)+e- ⟶ S-(g)

13. Ionisation enthalpy is an _____ process.

(a)

exothermic

(b)

endothermic

(c)

reversible

(d)

both (a) and (b)

14. Among the elements Ca, Mg, P and CI the order of increasing atomic radii is:

(a)

Mg < Ca < Cl < P

(b)

Cl < P < Mg < Ca

(c)

p < Cl < Ca < Mg

(d)

Ca < mg < P < Cl

15. The chemical symbol of carbon and cobalt are______

(a)

Ca and CO

(b)

Ca and Cl

(c)

C and CO

(d)

Cr and Cb

16. 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.

17. Which one of the following is a universal solvent?

(a)

Alcohol

(b)

Ether

(c)

CCl4

(d)

Water

18. Why Cs and K are used as electrodes in photoelectric cells

(a)

Due to their less ionisation energy

(b)

Due to high ionisation energy

(c)

Due to diagonal relationship

(d)

None of these

19. Consider the reaction where KP = 0.5 at a particular temperature
PCl5(g) ⇌ PCl3 (g) + Cl2 (g)
if the three gases are mixed in a container so that the partial pressure of each gas is initially 1 atm, then which one of the following is true

(a)

more PCl3 will be produced

(b)

more Cl2 will be produced

(c)

more PCl5 will be produced

(d)

none of these

20. The Henry's law constant for the solubility of Nitrogen gas in water at 350 K is 8 × 104 atm. The mole fraction of nitrogen in air is 0.5. The number of moles of Nitrogen from air dissolved in 10 moles of water at 350K and 4 atm pressure is

(a)

4 x 10-4

(b)

4 x 104

(c)

2 x 10-2

(d)

2.5 x 10-4

21. Equimolal aqueous solutions of NaCl and KCl are prepared. If the freezing point of NaCl is –2oC, the freezing point of KCl solution is expected to be

(a)

-2oC

(b)

-4oC

(c)

-1oC

(d)

0oC

22. The ratio of number of sigma (σ) and pi (л) bonds in 2- butynal is

(a)

8/3

(b)

5/3

(c)

8/2

(d)

9/2

23. Hybridisation of central atom in PClinvolves the mixing of orbitals

(a)

s, px, py, dx2 , dx2-y2

(b)

s, px . py, pxy . dx2-y2

(c)

s, px, py, pz, dx2-y2

(d)

s, px, py, dxy, dx2-y2

24. Structure of the compound whose IUPAC name is 5,6 - dimethylhept - 2 - ene is

(a)

(b)

(c)

(d)

None of these

25. C -X bond is strongest in

(a)

Chloromethane

(b)

Iodomethane

(c)

Bromomethane

(d)

Fluoromethane