Structure of atom

Question 1

Conditions for electrical discharge of gases

Answer 1

Low pressure

High voltage

Question 2

Characteristics of cathode rays

Answer 2

Do not depend on nature of gas, material of electrodes

Question 3

Characteristics of anode rays

Answer 3

Depend on nature of gas

Question 4

Neutron discovery experiment

Answer 4

Bombarding thin sheet of Be with alpha particles

Question 5

Milikan’s oil drop exp principle:

Answer 5

Gravity, electric, viscous drag force act on drop. Charge can be calculated by measuring rate of fall

Question 6

Characteristics of X rays

Answer 6

High penetrating power

Not deflected by electric or magnetic field

Question 7

Penetrating power order for alpha beta gamma

Answer 7

alpha < beta < gamma

Question 8

Drawbacks of rutherford

Answer 8

e- should lose energy and spiral into nucleus

did not explain e distribution

Question 9

Solid is heated, variation of radiation frequency with inc in temp?

Answer 9

Increases

Red to blue

Question 10

Intensity vs wavelength graph

Answer 10

wavelength inc, intensity inc reaches max and then decreases

Higher graph means higher temp

Question 11

No of e depends on

Answer 11

intensity/brightness

Question 12

KE of e depends on

Answer 12

frequency only

Question 13

No of spectral lines emitted

Answer 13

(n2-n1+1)(n2-n1)/2

Question 14

wavenumber constant

Answer 14

1.096 *10^7 m^-1

Question 15

Energy constant

Answer 15

2.18 * 10^-18J

Question 16

Frequency constant

Answer 16

3.29 * 10^15 Hz

Question 17

Probability of finding electron is directly proportional to?

Answer 17

(psi)^2

called probability density

Question 18

Graph of (psi)^2 vs r, how to identify which orbital

Answer 18

Number of nodes = n-l-1 (radial nodes)

every time graph touches x axis it is a node(radial node)

Question 19

Aufbau, Hund, Pauli

Answer 19

Aufbau: Filling starts from lower energy level
Pauli: Electrons in same orbital have opp spin
Hund: Pairing happens only after all orbitals are occupied

Question 20

Exchange energy is max at?

Answer 20

Half filled and fully filled