Is it possible to determine resonance structures.....or no? I understand what it is but I am not sure how the drawings come about or even how to recognize them.
It's mostly a little practice and looking for other ways to write Lewis electron dot structures. Basically, here are the steps.
1. Determine the number of electrons available. This part is easy.
2. Determine how many electrons are needed based on the octet rule. This is not hard BUT not all compounds obey the octet rule.
3. Determine the number of bonds needed from 1 and 2.
4. Draw the Lewis electron dot structure.
5. See if any resonance structures can be drawn using the same number of bonds and the same number of electrons.
6. Determine the formal charge of each atom to help in deciding which structures are most likely.
Try this on something like carbonate 2- ion or nitrate 1- ion. You will see that it is obvious that the double bond needed can be shifted to any of the oxygen atoms.
Yes, it is indeed possible to determine resonance structures. Resonance structures are alternative Lewis structures that can be drawn for a molecule or ion by moving electrons around. They are used to represent the delocalization of electrons in molecules and ions.
To determine resonance structures, there are a few steps you can follow:
1. Identify the molecule or ion: Start by identifying the central atom and the surrounding atoms.
2. Count the total number of valence electrons: Add up the valence electrons of each atom in the molecule or ion. Remember to account for any charges. For example, if the molecule has a positive charge, subtract one electron; if it has a negative charge, add one electron.
3. Draw the skeletal structure: Connect the atoms using single bonds to form the skeletal structure of the molecule or ion, representing the bonding arrangement.
4. Distribute the remaining electrons: Distribute the remaining valence electrons to satisfy the octet rule for each atom. Start with the outer atoms, and then place any remaining electrons on the central atom.
5. Check for the presence of extra electrons: If there are any extra electrons after satisfying the octet rule, you can begin to move them around to create resonance structures.
6. Move electrons: Start by moving a lone pair of electrons from a localized bond to form a multiple bond, and vice versa. You can only move electrons that are involved in π (pi) bonds or lone pairs.
7. Draw additional resonance structures: Repeat the process of moving electrons until no new resonance structures can be generated. Remember, each resonance structure must obey the octet rule for each atom and maintain the same overall charge.
To recognize resonance structures, pay attention to the movement of electrons. Resonance structures have the same arrangement of atoms but differ in the placement of lone pairs and double (or triple) bonds. Look for patterns where electrons are being shifted, leading to the delocalization of charge or stability.
Remember, resonance structures are not individual molecules, but rather different representations of the same molecule or ion. They contribute to the overall molecular structure and properties.