Atoms Test - 57...

The distance between $$3^{rd}$$ & $$2^{nd}$$ Bohr orbit $$He^{+}$$ is 

The ratio of the radii of the first three Bohr orbit in H atom is 

The angular momentum of electron in 4th orbit of hydrogen atom is

In the Geiger - Marsden scattering experiment, find the distance of closest approach to the nucleus of a $$7.7Mev$$ $$\alpha$$ - particle before it comes momentaily to rest and reverses its direction. ($$'Z'$$ for gold nucleus $$= 79$$)

According to Bohr's model, if the kinetic energy of an  electron in $$2^{nd}$$ orbit of $$He^{+}$$ is $$x$$, then what should be the ionisaion energy of the electron revolving in $$3^{rd}$$ orbit of $$m^{5+} ions>$$

Energy of an electron is given by $$E=-2.178\times { 10 }^{ -18 }J\left( \dfrac { { Z }^{ 2 } }{ { n }^{ 2 } }  \right) $$ Wavelength of light required to excite an electron in an hydrogen atom from level n=1 to n=2 will be:-`
$$\left( h=6.62\times { 10 }^{ -34 }Js\quad and\quad c=3.0\times { 10 }^{ 8 }{ ms }^{ -1 } \right) $$

The difference between the wave number of $${ 1 }^{ st }$$ line of Balmer series of paschen series for $${ Li }^{ 2+ }ion$$ is:

Two electron separated by a distance $$r$$ experiences force $$F$$ between them . Then force between a proton and a singly ionized helium atom separated by a distance $$2r$$ is

Hydrogen atom in ground state is excited by a monochromatic radiation of $$\lambda =975\mathring { A } $$ Number of spectral lines in the resulting spectrum emitted will be 

The ratio of the frequencies of the long wavelength limits of the Lyman and Balmer series of hydrogen is: