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what are ISOELECTRONIC SPECIES and give examples.
Why is Fe3+ ion more stable than Fe2+ ion?
drawbacks of j j thomson atomic models
what does bombarding means??
a block of mass 'm' is placed on a smooth wedge of inclination of theta.the whole system is accelerated horizontally so that the block does not slip on the wedge.The force exerted by the wedge on block has a magnitude.
explain pauli's exclusion principle
velocity of electron in 3rd shell of Li+2is (c=velocity of light) 1. 1/137 c
2.1/274 c
3.2/137c
What's is hunds rule of maximum multiplicity Explain with many example and how is it different from the other
The no. Of electrons in 2gm ion of nitrate NO3 is ?
Calculate the energy associated with the 1st orbit of He+. What is the radius of the orbit?
Pls give the answer in steps..!
Why is electron gain enthalpy of chlorine is more than fluorine?
calculate mass of photon with wavelength 3.6 A . ?
why electon cannot exist in the nucleus?
ratio of e/m of electron and alpha particle is
Q.) Which transition of Li2+ is associated with same energy change as n=6 to n=4 transition in He+.
(I) n=3 to n=1 (II) n=8 to n=6 ( III) n=9 to n=6 (IV) n=2 to n=1
Calculate the wave number for the longest wavelength transition in the Balmer series of atomic hydrogen.
Write the electronic configuration of (i) Mn4+, (ii) Fe3+ (iii) Cr2+ and Zn2+ Mention the number of
unpaired electrons in each case.
What is the derivation of the radius of the nth orbit in bohr's model?
the formula is Rn = (4πε0)n2h2 / 4π2me2
In an atom two electrons move around the nucleus in circular orbit of radii R and 4R. The ratio of time taken by them to complete one revolution is
(a)1:8 (b)4:1 (c)1:4 (d)8:7
Calculate the wavelength of first and last line in the Balmer series of Hydrogen spectrum.
Why do half filled and completely filled orbitals have extra stability?
state Heisenberg's Uncertainty principle?
Light of wavelength 5000 A falls o n a metal surface of work function 1.9 eV . Find (a ) the energy of photons (b) kinetic energy of photoelectrons . [1eV = 1.6 * 10 (-19) J ] please answer fast
why copper and chromium have extra stability?
Give any 5 differences between ORBIT ORBITALS
The mass of an electron is 9.1x10-31kg.If its kinetic energy is 3.0x10-25J.CALCULATE ITS WAVELENGTH........
Which quantum number determines (i) energy of electron(ii) Orientation oforbitals.
why are bohr's orbits called stationary states?
calculate the energy and frequency of light required to excite an electron in hydrogen atom from first energy level to fourth energy level
the wavelength of the third line in the Paschen series of hydrogen spectra spectra is ?
In this type of question n1=3 but from where n2 =6 come it is not given
tell me how to solve numerical based on line in other spectral series of hydrogen too
calculate the mass and charge of one mole of electron?
WHAT is the no of molecules present in 1 ml of water vapour at STP?? I did like this
1 mole of h2o at STP has 22.4l volume ie...6.022 *1023 molecules has 22.4l
So 1/1000 l will have x molecules
By diving x=o.26 * 1020 .This is wat I got is this correct??help pls...
Find (a) the total number and (b) the total mass of neutrons in 7 mg of 14C.
(Assume that mass of a neutron = 1.675 × 10–27 kg).
With what velocity should an alpha particle travel towards the nucleus of a copper atom so as to arrive at a distance 10-13 m from the nucleus of a copper atom?
Explain and derive schrodinger wave equation for hydrogen and hydrogen like species.
Calculate the mass of a photon of sodium light having wavelength 5894 A0 & velocity as 3108 ms - 1
Cathode rays are produced only when the pressure of the gas inside the discharge tube is very very low. Give reason
Calculate energy of one mole of photons
Explain the meaning of the symbol 4d6
how many nodal planes are there in dz2 orbital ??? ( most of the authors wrote 2 , bt sme renowned experts wrote ZERO ) so m confused between zero n two ???
what are the frequency and wavelenght of a photon emitted during a transition from n=5 state to n=2 state in the hydrogen atom
what is the difference between 2O and O2
How many photons of light having a wavelength 400 nano meter are necessary to provide 1 joule of energy?
DIFFERENCE BETWEEN WAVE AND PARTICLE NATURE? IN BRIEF
What is photoelectric effect?
calculate the no. of protons in 10g of CaCO3 . NA=6.02* 1023.
with the help of pauli's exclusion principle and the concept of atomic numbers for orbitals show that an M shell cannot accomodate more than 18 electrons ...... urgently required plese by tomorrow if possible
correct set of quantum number for unpaire electron in chlorine
Two particles A and B are in motion. If the wavelength associated with particle A is 5x10^-8m, calculate wavelength associated with B if its momentum is half of A
The kinetic energy of a subatomic particle is 5.85x10^-25 J. Calculate the frequency of the particular wave.
1/5800*10-10m
What is black body radiation?
A 100 watt bulb emits monochromatic light of wavelength 400 nm. Calculate
URGENT:
An electron has a velocity of 300 m s-1 that is accurate to 0.01%. With what accuracy can one locate the position of this electron ( mass of electron = 9.1 * 10-31 kg )?
What are planck's postulates..??
Electromagnetic radiation of wavelength 242 nm is just sufficient to ionise the sodium atom. Calculate the ionisation energy of sodium in kJ mol–1.
natural abundance of C12 and C13 isotopes of carbon are 99% and 1% respectively.assuming they only contribute to the molar weight of C2F4 ,what is the percentage of C2F4 having molar mass 101?
what is the difference between absorption and emission spectrum
calculate the wavelength , frequency nd wavenumber of a light wave whose period is 2.0 x 10-10
E.g: 9876543210, 01112345678
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Syllabus
what are ISOELECTRONIC SPECIES and give examples.
Why is Fe3+ ion more stable than Fe2+ ion?
drawbacks of j j thomson atomic models
what does bombarding means??
a block of mass 'm' is placed on a smooth wedge of inclination of theta.the whole system is accelerated horizontally so that the block does not slip on the wedge.The force exerted by the wedge on block has a magnitude.
explain pauli's exclusion principle
velocity of electron in 3rd shell of Li+2is (c=velocity of light)
1. 1/137 c
2.1/274 c
3.2/137c
What's is hunds rule of maximum multiplicity Explain with many example and how is it different from the other
The no. Of electrons in 2gm ion of nitrate NO3 is ?
Calculate the energy associated with the 1st orbit of He+. What is the radius of the orbit?
Pls give the answer in steps..!
[1] d [2] 13.5d [3] 1.5d [4] 0.07d
Why is electron gain enthalpy of chlorine is more than fluorine?
A)Gama line in Lyman series in H--UV
B)Beta line in Balmer series in He+---UV
C)Delta line in Balmer series in H---visisble
D)Delta line in Paschen series in H--- Infrared
Answer is all the options are correct but I don't understand how B is correct. Also explain the others. How can a beta line in Balmer series in He+ is UV. How do I know if it will be UV. It must be visible?
calculate mass of photon with wavelength 3.6 A . ?
aplha rays
H+ rays
D+ rays
All have equal
why electon cannot exist in the nucleus?
(A) 4.8
(b) 1.6
(c) 3.2
(d) 6.4
ratio of e/m of electron and alpha particle is
i) The nature of cathode rays does not depend on the nature of gas taken in discharge tube.
ii) Anode rays cause sputtering when incident on metal.
iii) Cathode rays produce X rays when they are abruptly stopped by metallic obstacle and nature of X rays produced depends only on metal and not on cathode rays
iv) The degree of deflection in same magnetic field vary in case of anode rays produced from different gases taken in discharge tube.
Q.) Which transition of Li2+ is associated with same energy change as n=6 to n=4 transition in He+.
(I) n=3 to n=1 (II) n=8 to n=6 ( III) n=9 to n=6 (IV) n=2 to n=1
Calculate the wave number for the longest wavelength transition in the Balmer series of atomic hydrogen.
Write the electronic configuration of (i) Mn4+, (ii) Fe3+ (iii) Cr2+ and Zn2+ Mention the number of
unpaired electrons in each case.
i) alpha rays
ii) H+ rays
iii) D+ ray
iv) All have equal
What is the derivation of the radius of the nth orbit in bohr's model?
the formula is Rn = (4πε0)n2h2 / 4π2me2
In an atom two electrons move around the nucleus in circular orbit of radii R and 4R. The ratio of time taken by them to complete one revolution is
(a)1:8 (b)4:1 (c)1:4 (d)8:7
Calculate the wavelength of first and last line in the Balmer series of Hydrogen spectrum.
i) 9/4 v
ii) 4/9 v
iii) v
iv) None of these
Why do half filled and completely filled orbitals have extra stability?
state Heisenberg's Uncertainty principle?
Light of wavelength 5000 A falls o n a metal surface of work function 1.9 eV . Find (a ) the energy of photons (b) kinetic energy of photoelectrons . [1eV = 1.6 * 10 (-19) J ] please answer fast
why copper and chromium have extra stability?
Give any 5 differences between ORBIT ORBITALS
The mass of an electron is 9.1x10-31kg.If its kinetic energy is 3.0x10-25J.CALCULATE ITS WAVELENGTH........
Which quantum number determines (i) energy of electron(ii) Orientation oforbitals.
why are bohr's orbits called stationary states?
calculate the energy and frequency of light required to excite an electron in hydrogen atom from first energy level to fourth energy level
a) 2pi x
b) 6pi x
c)9x
d)x/3
the wavelength of the third line in the Paschen series of hydrogen spectra spectra is ?
In this type of question n1=3 but from where n2 =6 come it is not given
tell me how to solve numerical based on line in other spectral series of hydrogen too
calculate the mass and charge of one mole of electron?
WHAT is the no of molecules present in 1 ml of water vapour at STP?? I did like this
1 mole of h2o at STP has 22.4l volume ie...6.022 *1023 molecules has 22.4l
So 1/1000 l will have x molecules
By diving x=o.26 * 1020 .This is wat I got is this correct??help pls...
Find (a) the total number and (b) the total mass of neutrons in 7 mg of 14C.
(Assume that mass of a neutron = 1.675 × 10–27 kg).
With what velocity should an alpha particle travel towards the nucleus of a copper atom so as to arrive at a distance 10-13 m from the nucleus of a copper atom?
Explain and derive schrodinger wave equation for hydrogen and hydrogen like species.
Calculate the mass of a photon of sodium light having wavelength 5894 A0 & velocity as 3
108 ms - 1
Cathode rays are produced only when the pressure of the gas inside the discharge tube is very very low. Give reason
Calculate energy of one mole of photons
Explain the meaning of the symbol 4d6
how many nodal planes are there in dz2 orbital ??? ( most of the authors wrote 2 , bt sme renowned experts wrote ZERO ) so m confused between zero n two ???
A. Azimuthal quantum number
B. Magnetic quantum number
C. Principal quantum number
D. Spin quantum number
what are the frequency and wavelenght of a photon emitted during a transition from n=5 state to n=2 state in the hydrogen atom
what is the difference between 2O and O2
How many photons of light having a wavelength 400 nano meter are necessary to provide 1 joule of energy?
DIFFERENCE BETWEEN WAVE AND PARTICLE NATURE? IN BRIEF
What is photoelectric effect?
(A) -particle
(B) proton
(C) deutron
(D) neutron
calculate the no. of protons in 10g of CaCO3 . NA=6.02* 1023.
with the help of pauli's exclusion principle and the concept of atomic numbers for orbitals show that an M shell cannot accomodate more than 18 electrons ...... urgently required plese by tomorrow if possible
correct set of quantum number for unpaire electron in chlorine
Two particles A and B are in motion. If the wavelength associated with particle A is 5x10^-8m, calculate wavelength associated with B if its momentum is half of A
The kinetic energy of a subatomic particle is 5.85x10^-25 J. Calculate the frequency of the particular wave.
1/5800*10-10m
What is black body radiation?
A 100 watt bulb emits monochromatic light of wavelength 400 nm. Calculate
the number of photons emitted per second by the bulb.URGENT:
An electron has a velocity of 300 m s-1 that is accurate to 0.01%. With what accuracy can one locate the position of this electron ( mass of electron = 9.1 * 10-31 kg )?
What are planck's postulates..??
Electromagnetic radiation of wavelength 242 nm is just sufficient to ionise the sodium atom. Calculate the ionisation energy of sodium in kJ mol–1.
natural abundance of C12 and C13 isotopes of carbon are 99% and 1% respectively.assuming they only contribute to the molar weight of C2F4 ,what is the percentage of C2F4 having molar mass 101?
a) 20 x 1014 Hz
b) 10 x 1014 Hz
c) 5 x 1014 Hz
d) 1 x 1014 Hz
what is the difference between absorption and emission spectrum
Ans= 5.4
calculate the wavelength , frequency nd wavenumber of a light wave whose period is 2.0 x 10-10
What Michael Faraday found in his experiment ?
Who did the first experiment to find (e-)?
I think when we open 11-science , then open structure of atom , then its concept ,, there is wrongly written that ,, {discovery of atom (Michael Faraday's cathode ray tube experiment)} , please check it if it's wrong , and please ans these three question in one forum !!