subject: Nuclear Chemistry Notes [print this page] Introduction Introduction
Atom is the ultimate unit of an element.Every atom has a nucleus in its center. The study of the nucleus is called nuclear chemistry. The study of nucleus gained momentum in former part of 20th century.The nucleus is occupied by positively charged protons.Protons were the first species in nucleus to be discovered.
Why?
Nuclear chemistry is the subdiscipline of chemistry that is concerned with changes in the nucleus of elements. These changes are the source of radioactivity and nuclear power. Since radioactivity is associated with nuclear power generation, the concomitant disposal of radioactive waste, and some medical procedures, everyone should have a fundamental understanding of radioactivity and nuclear transformations in order to evaluate and discuss these issues intelligently and objectively.
Learning Objectives
- Identify how the concentration of radioactive material changes with time.
- Determine nuclear binding energies and the amount of energy released in a
nuclear reaction.
Success Criteria
- Determine the amount of radioactive material remaining after some period of time.
- Correctly use the relationship between energy and mass to calculate nuclear binding energies and the energy released in nuclear reactions.
Thereafter neutrons discovered by Chadwick in 1935.Neutrons are neutral in character and they are also part of the nucleus.There are details of nuclear chemistry notes given below.
Detailed Information in Nuclear Chemistry Notes:
The masses of a proton and neutron are 1.67262158 10^-27 kilogram and 1,6749 x 10^(-27) kg respectively.
The unit a.m.u. used in nuclear chemistry is the 1/12th mass of a 12C.atom.
1 amu is also written simply as 'u '.
1.660538782(83) 10^27 u = 1kg.
Generally the number of neutrons would be the same as that of protons.However in some elements it is not so.They atomic number is same but not the mass number.Such elements are called isotopes.
In some cases the mass number s are same but not the atomic numbers,they are called isobars. These are some facts given under nuclear chemistry notes
Energy in Nucleus in Nuclear Chemistry Notes :
Certain unstable nuclei emit rays.This is called as radioactivity.The rays emitted are called alpha,beta and gamma .The radioactivity is hazardous in effect and cause cancer too.
It was observed that the mass of the protons and neutrons together is more than the mass of the nucleus.This difference is called mass defect and Einstein attributed this difference to binding energy.
Binding energy binds the protons of a nucleus together in the nucleus which would otherwise repel each other and would burst. the nucleus.
This information was used to harness the binding energy by breaking the nuclei.
So nuclear fission was that reaction used in an atom bomb which used this tremendous energy.
Einstein gave the relationship by his famous equation
E=mc^2
where m is mass converted to energy and c is speed of light.
