Atomic structures - ii

Question 1

The energy of electron moving with velocity v is

Answer 1

En = m(rest) / sq root [1- (v/c)]

Question 2

The mass of an electron whose velocity is equal to the speed of light is

Answer 2

infinite

Question 3

mass of electron =

Answer 3

1/ 1837 th times the mass of hydrogen

Question 4

if in a discharge tube H2 is used, the positive ray is known as

Answer 4

proton/canal ray

Question 5

if in a discharge tube, other elements are used, the ray is known as:

Answer 5

positive ray

Question 6

The magnetic quantum number depends on:

Answer 6

Zeeman effect

Question 7

does the value of e/m depend on the nature of the gas used in the discharge tube?

Answer 7

no

Question 8

Positron was discovered by

Answer 8

Anderson
it combines with electron producing gamma rays

Question 9

Pi-meson and mu-meson were discovered by

Answer 9

Yukawa
it lies between proton and neutron

Question 10

Neutrinos and antineutrinos were discovered by:

Answer 10

Femi
It has mass and charge nearly equal to zero

Question 11

isosteres?

Answer 11

molecules having the same at. no and electrons

Question 12

rutherford discovered?

Answer 12

nucleus of an atom

Question 13

the rutherford scattering experiment uses:

Answer 13

helium nucleus and not helium atoms

Question 14

alpha particles are

Answer 14

helium neucleus

Question 15

calculation of the highest energy is carried out by:

Answer 15

(n + l) n = principle quantum number and l = azimuth quantum number

Question 16

Quantum theory explains that radiant energy is absorbed

Answer 16

not continuously but discontinuously

Question 17

what is a photon?

Answer 17

a quanta of light ray is called a photon
it has NO MASS

Question 18

relationship between rydberg’s constant and electron is:

Answer 18

R is directly proportional to the mass of electron

Question 19

the angular momentum of the spin of all electrons is:

Answer 19

h/2pi sq root s(s+1) or
(sq root 3)*h /4

Question 20

a node is calculated by:

Answer 20

n-l-1

Question 21

the rays of electrons are known as :

Answer 21

beta rays

Question 22

which isotope of hydrogen is radioactive?

Answer 22

tritium

Question 23

the value of kinetic energy is equal to :
in terms of charge and acceleration

Answer 23

Relative charge× accelerating potential

Question 24

what does Millikan’s oil drop method experiment on?

Answer 24

to prove the charge of an electron

Question 25

The potential energy of an electron in the nth orbital is calculated by

Answer 25

2* (Energy)
where energy is given by;
-13.6 z^2/ n^2

Question 26

Azimuthal quantum number is also known as

Answer 26

Subsidiary quantum number

Question 27

total spin is calculated by the formula

Answer 27

+/- 1/2 times n
where n= principal quantum number