8/12/2019 Xi Chemistry ,Comprehensive Chemistry
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1. What is the value of e/m for the particles in cathode rays?2.
What are isotones?3. What are the possible values of m for an
electron in 3d sub-shell?4. What is the shape of 3s orbital? How
many nodes are there in it.5. What are degenerate orbitals?6. What
is the number of d electrons in ion?7. Which of the following
orbitals are not possible? 3f, 4p, 2d, 7p.8. Which are the possible
values of n, l and m for 3p orbital?9. Compare the mass and charge
of the three fundamental sub-atomic particles.10.From what
observations do you derive the following inferences?
(i) The most of the space inside the atom is empty.(ii) The
volume of the nucleus is very small.(iii) Anode rays consist of
positively charged particles.
11.Why was Thomsons model of atom discarded and replaced by
Rutherfords model? Whyis Rutherfords model also called the nuclear
model of atom?
12.The energy of a photon is 3.98 J. What is its wavelength in
nm?13.The threshold frequency for a metal is 7.0 Calculate the
kinetic energy of
an electron emitted when radiation of frequency v = 1.0
hits the metal.14.Give various postulates of Bohrs atomic model.
How does it explain emission spectrum
of hydrogen?
15.Why are there so many lines in hydrogen spectrum although
there is only one electron inits atom?
16.What is the wavelength of a photon (in nm) emitted during a
transition from the state to the state in the hydrogen atom?
17.Calculate the energy associated with the first orbit of
. What is the radius of this
orbit?
18.Calculate the wavelength of the de-Broglie wave associated
with an electron havingkinetic energy 3.0 J. Mass of an electron =
9.1 kg.
19.State and explain Heisenbergs uncertainty principle.
