HNO3 (Nitric acid) lewis stricture is drawn step by step by using valence electrons of each element. In the lewis structure of nitric acid, there is a +1 charge on nitrogen atom and one double bond between nitrogen and one oxygen atom.
There is a N=O bond in nitric acid lewis structure. There are no lone pairs on nitrogen atom and also there are charges on one oxygen atom and nitrogen atom. You can see those signs in the following figure.
There are some steps to follow to draw the HNO3 lewis structure and those steps are explained in detail in this tutorial.
Important: Drawing correct lewis structure is important to draw resonance structures correctly.
Hydrogen is a group IA element and has one electron in its last shell. Nitrogen is located at group VA and has five electrons in its valence shell. Oxygen is a group VIA element in the periodic table and contains six electrons. Now we know how many electrons are includes in valence shells of each atom.
Total valance electrons pairs = σ bonds + π bonds + lone pairs at valence shells
Total electron pairs are determined by dividing the number total valence electrons by two. For, HNO3, Total pairs of electrons are 12 in their valence shells.
To be the center atom, ability of having greater valance is important. Then, from hydrogen, nitrogen and oxygen, which atom has the highest valence. Nitrogen can show valence five which is greater than maximum valence of oxygen two. Therefore, nitrogen atom should be the center atom of HNO3.
After determining the center atom and sketch of HNO3, we should start to mark lone pairs on atoms.
After, marking electron pairs on atoms, we should mark charges of each atom. Two oxygen atoms will get a -1 charge and nitrogen atom get a +2 charge.
Best lewis structure should have low charges on atoms.
In the new structure of HNO3, charges are reduced. Therefore, this is the best lewis structure we can draw for HNO3.
There are no lone pairs on nitrogen atom. There are two N-O bonds and one N=O bond. So, there is +1 charge on nitrogen atom.
Two oxygen atoms have charges (-1 for those oxygen atom).
No. Clearly they are different because there is one more oxygen atom in HNO3. Therefore, there should be another bond between nitrogen and that oxygen atom.