00:01
In this video, we are going to find out the number of radial nodes for the given orbitals.
00:05
So, firstly, we need to understand what does it mean by our node? so, node means a point where the probability of finding the electron is zero.
00:16
So we can write it as electron probability is equals to zero.
00:23
And now we can here say that there are two types of node.
00:28
So, one is radial node and the other one is angular node.
00:33
So we can write this very, we can say segregation as well and it will be here angular.
00:41
Now, we can here mention that radial nodes are called as nodal reasons and angular nodes are called as nodal planes.
00:51
So we can write this very information also that it is our nodal planes and this is our nodal region.
00:58
So this very name will help us to understand the difference between them.
01:03
And hence we can here write that the radial nodes are the spheres that occur when the radial wave function of the orbital is equal to 0.
01:14
So the formula for number of radial nodes is equal to here.
01:19
We can say that it will be number of and then here we are having radial and then it will be here nodes.
01:26
So this is here equals to n minus l minus 1 where n is basically the total number of we can say nodes and l is the number of angular nodes.
01:41
So here let us see how we can find the answer for this very question.
01:45
So in the first part of this very problem we are going to talk about 2s orbital.
01:50
So here we can write that for 2s the number of nodes will be here equals to.
01:56
2.
01:57
Basically, n is the principal quantum number which also denotes the number of nodes.
02:02
And hence, the number of radial nodes, which can be denoted, suppose we are denoting it as r.
02:08
So this will be here equals to n minus l, minus 1.
02:13
So what is the value of l for 2s orbital? that is, angular node will be here equal to 0.
02:20
So this very value will be here equals to 2 minus 0 minus 1, that is equals to 1.
02:25
So there is one radial node in 2s orbital and this will be the first case.
02:31
Now here we have the second one which is basically 4s orbital.
02:36
So we can write for 4s orbital and this will be here n value is equal to 4.
02:43
L value for s orbital is equal to 0 and this will be here basically that is number of radial nodes will be equals to n minus l minus 1 that comes out to be equals to 4 minus 1 that is equal to 3.
02:57
So this is the answer for the second part...