#### 11th Standard Chemistry English Medium Free Online Test One Mark Questions with Answer Key 2020 - Part Ten

11th Standard

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Chemistry

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

25 x 1 = 25
1. What is the mass of precipitate formed when 50 ml of 8.5 % solution of AgNO3 is mixed with 100 ml of 1.865 % potassium chloride solution?

(a)

3.59g

(b)

7g

(c)

14 g

(d)

28 g

2. Which of the following electronic configuration represent the element in ground state?

(a)

1s22s12p1

(b)

1s22s22p1

(c)

1s22s12px12py12pz1

(d)

1s22s22p63s23px13py13pz13d1

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

(a)

zero

(b)

0.50

(c)

0.75

(d)

0.90

4. J. J. Thomson's cathode ray experiment revealed that atoms consist of

(a)

electrons

(b)

protons

(c)

neutrons

(d)

photons

5. Consider the following statements
1.$\lambda$ .= h / mv is valid only when the particle travels at speed much less than the speed of light.
2. Einstein's mass-energy relationship is E=mc2
3. The angular momentum (mvr) ofthe electron must be equal to an integral multiple of h/4$\pi$ . Which of the following statementts) given above is/ are correct?

(a)

1&3

(b)

Only 1

(c)

1 & 2

(d)

1, 2 & 3

6. Which is the lightest among the following?

(a)

An atom of hydrogen

(b)

An electron

(c)

A neutron

(d)

A proton

7. The radius of nucleus is approximately __ times smaller than the radius of atom.

(a)

1,00,000

(b)

5,000

(c)

10,000

(d)

200

8. Which of the following conclusions could not be derived from Rutherford's $\alpha$-particle scattering experiment?

(a)

Most of the space in the atom is empty.

(b)

The radius of the atom is about 10-10 m while that of the nucleus is 10-15 m

(c)

Electrons move in a circular path of fixed energy called orbits.

(d)

Nucleus and the electrons are held together by electrostatic force of attraction

9. The value of Bohr radius for hydrogen atom is

(a)

0.529 $\times$ 10-8 cm

(b)

0.529 $\times$ 10-10 cm

(c)

0.529 $\times$ 10-12 cm

(d)

0.529 $\times$ 10-12 cm

10. According to Bohr's theory angular momentum of an electron in 6th orbit is

(a)

$2.5\frac { h }{ \pi }$

(b)

$6\frac { h }{ \pi }$

(c)

$3\frac { h }{ \pi }$

(d)

$\frac { 2.5h }{ 2\pi }$

11. What will be the wavelength of a ball of mass 0.1 kg moving with a velocity of 10ms-1?

(a)

6.62 $\times$ 10-34m

(b)

6.626 $\times$ 1034m

(c)

6.626 $\times$ 10-34m

(d)

6.626 $\times$ 1034m

12. Assertion (A): Bohr's orbits are also called stationary states.
Reason (R): Electrons are stationary is an orbit.

(a)

Both A and R are true and R is the correct explanation ofA

(b)

Both A and R are true but Ris not the correct explanation of A

(c)

A is true but R is false

(d)

Both A and R are false

13. Given that the energy of the first Bohr about is -1312 kJ mol-1, the ionisation energy of hydrogen atom is:

(a)

-1312 kJ

(b)

1312 kJ

(c)

21.8 x 10-20 J

(d)

2.18 x 10-19 J

14. Which of the following expressions represents the electron probability function?

(a)

$4\pi r dr{ \Psi }^{ 2 }$

(b)

$4\pi r^2 dr{ \Psi }$

(c)

$4\pi r^2 dr{ \Psi }^{ 2 }$

(d)

$4\pi r dr{ \Psi }$

15. Maximum deviations from ideal gas is expected from:

(a)

H2(g)

(b)

N2(g)

(c)

CH4(g)

(d)

NH3(g)

16. C(diamond) ) ⟶ C(graphite), ΔH = -ve, this indicates that

(a)

graphite is more stable than diamond

(b)

graphite has more energy than diamond

(c)

both are equally stable

(d)

stability cannot be predicted

17. Shape of ClF3 is

(a)

Planar triangular

(b)

Pyramidal

(c)

'T' Shaped

(d)

none of these

18. The IUPAC name of the compound  is

(a)

3 – Ethyl -2– hexene

(b)

3 – Propyl -3– hexene

(c)

4 – Ethyl – 4 – hexene

(d)

3 – Propyl -2-hexene

19. A sample of 0.5g of an organic compound was treated according to Kjeldahl’s method. The ammonia evolved was absorbed in 50mL of 0.5M H2SO4. The remaining acid after neutralisation by ammonia consumed 80mL of 0.5 MNaOH, The percentage of nitrogen in the organic compound is.

(a)

14%

(b)

28%

(c)

42%

(d)

56%

20. Hyper Conjugation is also known as

(a)

no bond resonance

(b)

Baker - nathan effect

(c)

both (a)and (b)

(d)

none of these

21. An alkyl bromide (A) reacts with sodium in ether to form 4, 5– diethyloctane, the compound (A) is

(a)

CH3 (CH2)3 Br

(b)

CH3(CH2)5 Br

(c)

CH3(CH2)3 CH(Br)CH3

(d)

${ CH }_{ 3 }-{ \left( { CH }_{ 2 } \right) }_{ 3 }-CH\left( Br \right) -\underset { \overset { { | } }{ { CH }_{ 3 } } }{ { CH }_{ 3 } }$

22. In which of the following molecules, all atoms are co-planar

(a)

(b)

(c)

(d)

both (a) and (b)

23. In the reaction  X is ________.

(a)

(b)

(c)

(d)

24. Consider the reaction,
CH3CH2CH2Br + NaCN → CH3CH2CH2CN + NaBr
This reaction will be the fastest in

(a)

ethanol

(b)

methanol

(c)

DMF (N, N' – dimethyl formanide)

(d)

water