How to Figure Out How Many Electrons Atoms Share
- 1). Write down the structural formula for your molecule (if you haven't done so already). Remember that organic chemists often omit the hydrogens in a molecule and simply represent the carbon atoms as vertices between two lines (the point where two straight lines join), so if you see a structural formula like this, you can mentally add hydrogens to each carbon as needed until each carbon atom has a total of four bonds.
- 2). Look at the lines connecting atoms in your structural formula. These lines represent bonds between atoms.
- 3). Pick any two atoms in the molecule and determine how many lines connect them. If they are connected with one line only, they have a single bond and they share two electrons. If they are connected by two lines, they have a double-bond and they share four electrons. If they are connected by three lines, they have a triple bond and they share six electrons.
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