Short and sweet ,Step by step method to draw Lewis structures.

 These are the steps that  you should follow in order to draw a  Lewis structure

  • Select  the central atom
  • Draw the skeleton of the molecule
  • Calculate the total no. of valence electrons in the molecule.
  • Convert these total number of electrons in to pairs.
  • Subtract the number of  electron pairs equal to the number of bonds in the skeleton
  • Allocate remaining electrons first to the terminal atom  such that they acquire inert gas configuration.
  • If the central atom lacks an octet then convert single bonds in to double bond or triple bond .

Now as an example I would like to take phosphoryl chloride.

  • Now you want to find the central atom . Central atom is the one that posses lowest electronegativity out of other atoms 
                                        Here the phosphorous have  the lowest electronegativity.

  • Next you want to draw the skeleton of this compound . The image which is  appeared in below shows you a skleton of phosphoryl chloride. 

  • Now what you should do is  calculate the total number of valence electron of the molecule 
And if there is a charge on the compound what you want to do is ,

Now let's approach to the fourth step of  converting the electrons into pairs. To do so we want to divide 32 which is the no. of valence electrons in phosphoryl chloride.

The next step is to subtract the number of electron pairs equal to the  bonds in the skeleton.

Now allocate those electron pairs into terminal atoms. Then finally you will get 

If you have any doubt feel free to comment below.

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