Hope you have seen the previous post. Now you are acquainted with the basics of the actual IUPAC electronic configuration. In this post, we will proceed further with an example. We will try to determine the electronic configuration of potassium. The atomic number of potassium is 19. Now draw the algorithm.
1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f
6s 6p 6d
7s 7p
You must recall the capacity of each shell. now draw a diagonal ray passing through 1s. As the capacity of s shell is 2, therefore it will hold 2 electrons. Now move to the next shell. Draw a diagonal ray passing through 2s. It will hold 2 electrons. Now 4 electrons have been arranged in the shells. Now draw a diagonal passing through 2p and 3s. 6 electrons will be arranged in the p shell and 2 in the s shell. Therefore, total of 12 electrons are arranged. Now draw a diagonal passing through 3p and 4s. 6 electrons in p shell but now only 1 electron is remained to be arranged. Put the 1 electron in the s shell. Therefore the electronic configuration of potassium is written as 1s^2 2s^2 2p^6 3^2 3p^6 4s^1. So the electronic configuration of potassium is 3p^6 4s^1 (Usually last two terms are taken into consideration while expressing the electronic configuration.) If you check on internet you will find that the electronic configuration of potassium is 4^1. Try determining the electronic configuration of chlorine, aluminium. Don't turn towards transition elements because the way of arranging electrons in the shell is different for transition elements. We will learn them when you perfect the above mentioned method.
Take COPPER as an example for transition metal. Its atomic number is 29. Therefore the electronic configuration we receive when we follow the above method is : 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^9. So you will write the electronic configuration as 4s^2 3d^9. But it is wrong. A shell is also a bit stable if it is half filled. So try to get the shells to the most stable form. In this case, it can be done by shifting 1 electron form 4s shell to 3d shell. So we get 4s^1 3d^10. Here, the 4s shell is also somewhat stable and 3d shell is completely filled, so it is no doubt the most stable form. So the electronic configuration of iron is 3d^10 4s^1. The s shell must always be at the last when expressing the electronic configuration. This technique is very useful. Because if you surf on the net about the valency of copper, it has two valencies that are 1+ and 2+. This can be calculated through the new method because at first we got 2 electrons in the outermost shell that is 4s shell . Therefore one valency of copper is 2+ and at the end we got 1 electron in the outermost shell that is in the 4s shell. Therefore, it has valency 1+ .
Hope this has proved useful to you. Keep on trying with taking different elements and checking if you get the correct electronic configuration. Dont go for elements with very high atomic numbers because they have some different pattern for arranging electrons . If you have understood this pattern, then the next pattern will be very easy. We will learn about it in my next post. Till then bye bye and ask questions in the form of posts so that there can be exchange of more knowledge between us. Please subscribe
1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f
6s 6p 6d
7s 7p
You must recall the capacity of each shell. now draw a diagonal ray passing through 1s. As the capacity of s shell is 2, therefore it will hold 2 electrons. Now move to the next shell. Draw a diagonal ray passing through 2s. It will hold 2 electrons. Now 4 electrons have been arranged in the shells. Now draw a diagonal passing through 2p and 3s. 6 electrons will be arranged in the p shell and 2 in the s shell. Therefore, total of 12 electrons are arranged. Now draw a diagonal passing through 3p and 4s. 6 electrons in p shell but now only 1 electron is remained to be arranged. Put the 1 electron in the s shell. Therefore the electronic configuration of potassium is written as 1s^2 2s^2 2p^6 3^2 3p^6 4s^1. So the electronic configuration of potassium is 3p^6 4s^1 (Usually last two terms are taken into consideration while expressing the electronic configuration.) If you check on internet you will find that the electronic configuration of potassium is 4^1. Try determining the electronic configuration of chlorine, aluminium. Don't turn towards transition elements because the way of arranging electrons in the shell is different for transition elements. We will learn them when you perfect the above mentioned method.
Take COPPER as an example for transition metal. Its atomic number is 29. Therefore the electronic configuration we receive when we follow the above method is : 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^9. So you will write the electronic configuration as 4s^2 3d^9. But it is wrong. A shell is also a bit stable if it is half filled. So try to get the shells to the most stable form. In this case, it can be done by shifting 1 electron form 4s shell to 3d shell. So we get 4s^1 3d^10. Here, the 4s shell is also somewhat stable and 3d shell is completely filled, so it is no doubt the most stable form. So the electronic configuration of iron is 3d^10 4s^1. The s shell must always be at the last when expressing the electronic configuration. This technique is very useful. Because if you surf on the net about the valency of copper, it has two valencies that are 1+ and 2+. This can be calculated through the new method because at first we got 2 electrons in the outermost shell that is 4s shell . Therefore one valency of copper is 2+ and at the end we got 1 electron in the outermost shell that is in the 4s shell. Therefore, it has valency 1+ .
Hope this has proved useful to you. Keep on trying with taking different elements and checking if you get the correct electronic configuration. Dont go for elements with very high atomic numbers because they have some different pattern for arranging electrons . If you have understood this pattern, then the next pattern will be very easy. We will learn about it in my next post. Till then bye bye and ask questions in the form of posts so that there can be exchange of more knowledge between us. Please subscribe