How many lone pairs are on the central atom in bcl3? Express your answer numerically as an integer?
There are no lone pairs on the central atom.
If we draw the lewis structure, we can see that all Cl atoms are all connected to the B atom. Now Cl atoms has 7 electrons each on its outermost shell while B can donate 3 electrons. So by octet rule, each Cl will gain 1 electron each from the B atom. From the Lewis structure, we can see that there are actually No Lone pairs on the central atom.