Free help with homework

Why join Brainly?

  • ask questions about your assignment
  • get answers with explanations
  • find similar questions


To describe position & energy of electron in an atom, 4 no are required which are known as quantum no.
1)principal quantum no
2)azimuthal "   "
3)magnetic ''    ''
4)spin  ''    ''
The rules of e- configuration are
1)each orbit can accomodate a fixed no of e-  Max no of e- in an orbit is 2n²
2)e- are filled in increasing order of energy i.e. K<L<M<N
3)in the outermost shell of an atom, the max no of e- is 8 (octet) except in the first shell which can have the most 2 e- (duplet)
1 3 1

This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
The Quantum numbers are nothing but the term that is used to address the position of an electron in an atom.There are 4 quantum numbers.
1.Principal q.no:
It is the basic q.no which is used to represent ORBITS or ENERGY LEVELS.eg:l,m,n,o
2.Azimuthal q.no:
It describes the presence of ORBITALS in every orbits.eg:s,p,d,f
3.Magnetic q.no:
It represents the presence of ORIENTATION in every orbitals.eg:px,py,pz
4.Spin q.no:
It represents the two direction of spin by an electron.
It is based on HUND'S RULE of maximum multiplicity.
The rule states that while allowing electrons into each orbitals of p.If you have to fill 3 electrons in p orbitals you can fill each one at px,py and pz.If you have to fill the fourth electron then you should put it onto px orbital which already have an electron in it.So it must be compulsary that for you to fill atleast one at each.
The diagram will make you know the configuration better way.

1 3 1
The Brain
  • The Brain
  • Helper
Not sure about the answer?
Learn more with Brainly!
Having trouble with your homework?
Get free help!
  • 80% of questions are answered in under 10 minutes
  • Answers come with explanations, so that you can learn
  • Answer quality is ensured by our experts