2nd orbit is _______ away from nucleus of H-atom as compared to 1st orbit is
1.2-times
2.3-times
3.4-times
4.6 times
A fast moving neutron can eject from nitrogen
1.? = rays
2.? = rays
3.? = rays
4.electrons
All of the following were theorized by Bohr in his description of the atom except
1.Angular momentum of electrons in multiples of h/2?
2.Electrons revolve in discrete circular orbits
3.Energy of each electron is directly proportional to n2
4.Electrons radiate energy continuously in a given orbit.
Angle of deflection was studied by
1.Hitorff
2.Stoney
3.William Crookes
4.J.Perrin
Angular momentum of an electron
1.n2h/2?
2.nk2/2?
3.nh/4?
4.nh/2?
Atom cannot be divided into simple unitstheorized by
1.Rutherford
2.Dalton
3.Bohr
4.Schrodinger
Atom with higher atomic number produces X-rays of
1.Shorter wavelength
2.Larger wavelength
3.X-ray not produced
4.All are possible
Atomic orbits having same evergy are called
1.Degenerate orbitals
2.Bonding molecular orbitals
3.Anti bonding molecular orbitals
4.Half filled orbitals
Centrifugal forces are balanced in atom by
1.Attractive forces
2.Repulsive force
3.Electrons
4.Neutrons
Charge of electron was measured by
1.J.J Thomson
2.Millikan
3.Rutherford
4.Perrin
Colour of fluorescene produced by cathode rays depends upon
1.Temperature
2.Pressure
3.Volume
4.Composition of glass
Electronic configuration of K is
1.[Ar]4s2
2.[Ar]4s1
3.[Kr]5s1
4.[He]2s1
Free neutron changes into proton with the emission of
1.Neutrino
2.Electron
3.Both a & b
4.Meson
Increase in atomic number is observed during
1.Alpha emission
2.Beta emission
3.Both a & b
4.Radioactivity
Milikan used __________ in his atomizer
1.Milk
2.Positron
3.Neutron
4.None of above has such capability
Milikan used __________ in his atomizer
1.Milk
2.Honey
3.Oil
4.Water
Neutrons moving with an energy of 1.2 MeV are called
1.Fast neutrons
2.Slow neutrons
3.Moderate neutrons
4.All are possible
Pfund series are produced in the spectrum of hydrogen atom
1.when electrons jump down to 2nd- orbit
2.when electrons jump down to 3rd- orbit
3.when electrons jump down to 4th- orbit
4.when electrons jump down to 5th- orbit
Plancks equation is
1.E = mc2
2.mvr = nh/2?
3.E = h?
4.? = h/mv
Planks theory says energy is emitted
1.In continuous manner
2.Discontinuous manner
3.Simultaneously
4.In the form of heat
Positive rays are produced
1.By burning of gas
2.By cooling of the gas
3.By the bombardment of cathode rays on gas molecules
4.From anode like cathode rays produced from cathode
Positive rays give flash on
1.AgNO3 plate
2.AgCl plate
3.ZnO
4.ZnS
Pressure in gas discharge tube was kept
1.10 torr
2.1 torr
3.0.1 torr
4.0.01 torr
Quantum number which tells the energy of electron is
1.n
2.1
3.m
4.s
Radius of the third shell of H-atom is
1.5.761 A?
2.4.761 A?
3.6.671 A?
4.3.716 A?
Rutherford bombarded ______________ particles in discovery of nucleus
1.Gamma-rays
2.Alpha-rays
3.Beta-rays
4.X-rays
Rutherfords planet like structure was defective and unsatisfactory because
1.Moving e- accelerate towards the nucleus
2.Continuous spectrum
3.behavior of electron remain unexplained
4.all
Sommerfelds modification in Bohrs model is
1.Orbit is cylindrical
2.Orbit is elliptical
3.Orbit is longitudinal
4.Orbit is asymmetrical
Space around nucleus where finding probability of electrons is maximum is called
1.Orbital
2.Orbit is elliptical
3.subshell
4.Electron cloud
Spectrum is produced due to
1.Different wavelength
2.Different colours
3.Different intensities
4.all have little contribution
Splitting of spectral lines when atom is subjected to magnetic field is called
1.Zeemans effect
2.Starks effect
3.Photo electric effect
4.Compton effect
Splitting of spectral lines when atoms are subjected to strong electric filed is called
1.Zeeman effect
2.Stark effect
3.Photoelectric effect
4.Compton effect
The atomic number of an element having maximum number of unpaired electrons in p-subshell is
1.7
2.10
3.12
4.16
The correct electronic configuration of Cu is
1.[Ar]4s1
2.[Ar]4s2
3.[Ar]3d104s1
4.[Ar]3d94s2
The letters s p d and f are used to represent which quantum numbers
1.Principal
2.Azimuthal
3.Magnetic
4.Spin
The magnetic quantum number (QN) has its values determined directly by the value of
1.Principal (QN)
2.Azimuthal (QN)
3.Spin (QN)
4.Both a & b
The maximum number of electron in a sub shell with ? = 3fs
1.6
2.10
3.14
4.18
The maximum number of orbitals present in a subshell that is represented by Azimuthal quantum number = 3 will be
1.1
2.3
3.5
4.7
The number of fundamental particles in an atom of the lightest isotope carbon are
1.6
2.12
3.18
4.20
The relationship between energy of a photon of light and its frequency is given by
1.de-Broglie duel nature of matter
2.Bohrs model
3.Plancks Quantum theory
4.Rutherfords atomic model
The value of e/m ratio of electron is
1.6.02 x 1023 C/kg
2.1.7588 x 1020 C/kg
3.9.1095 x 10-31 C/kg
4.1.7588 x 1011 C/kg
The velocity of the photon
1.Is independent of wavelength
2.Depends upon source
3.Depends upon its frequency
4.Equals to the square of amplitude
Wavelength of electron was verified by
1.Moseley
2.Davisson and Germer
3.Einstein
4.Roentgen
When 6d orbital is complete the entering electron goes into
1.7f
2.7s
3.7p
4.7d
When an atom absorbs energy the lines in the spectrum will appear which are
1.Brighter
2.Darker
3.Colourless
4.Hard to locate
When electron jump into orbit 1 then series obtained is
1.Lyman
2.Paschen
3.Pfund
4.Brackett
When electrons collide with heavy metals than ______ are produced.
1.Beta-rays
2.Alpha-rays
3.X-rays
4.Gamma-rays
Which one is not true about cathode rays?
1.9.11x10-31 Kg
2.Cast shadow
3.Heat up the platinum foil
4.Cannot ionize
Which one of the following explain the shape of orbitals
1.Principal of quantum number
2.Azimuthal quantum number
3.Magnetic quantum number
4.Spin quantum number
____________ can expel proteons from paraffins
1.Electron
2.Positron
3.Neutron
4.None of above has such capability