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atomic structure

atomic structure

by shambhavi mishra -
Number of replies: 1
1.Iodine molecules dissociates into atoms after absorbing light of 4500 angstrom.If 1 quantum of radiation is absorbed by each molecule,calculate the kinetic energy of iodine atoms.(bond energy of iodine molecules=240kJ/mol) 2.Find out the value of electrostatic potential energy of 2 electrons separated by 3.0 angstrom in vacuum. 3.Calculate the velocity of an electron placed in the 2nd orbit of Li2+ ion.Also Calculate the number ofrevolutions per second that it makes around the nucleus.
In reply to shambhavi mishra

Re: atomic structure

by Sanyam Kapoor -
Part 1 : There's a slight correction in the question. It should be "molecule" not "molecules". Then you can proceed as:

The total energy provided is calculated by
E = hc/λ = 4.41 x Undetermined error: Undetermined error: Undetermined error: Undetermined error: @@10^-19@@ J
Energy absorbed by each atom :
E (atom) = 2.205 x Undetermined error: Undetermined error: Undetermined error: Undetermined error: @@10^-19@@ J

Now Bond Energy of each molecule (B) = 3.98 x Undetermined error: Undetermined error: Undetermined error: Undetermined error: @@10^-19@@ J
So, for each atom 1.99 x Undetermined error: Undetermined error: Undetermined error: Undetermined error: @@10^-19@@ J

So now
KE of each atom = E(atom) - B (atom)
                         = 2.15 x Undetermined error: @@10^-20@@ J
                        
Part 3 :
Since it is Hydrogen Like atom :
So you can apply
v = [ (2.18 x 10^6) x Z ]/n
where Z = 3 and n = 2

So, v = 3.27 x Undetermined error: @@10^6@@ m/s

The number of revolutions per second in a particular orbit is always equal to the number of orbit.
Hence number of revolutions per second are 2.