(b) How many bonding electrons are in the structure?

Video transcript

welcome back everyone in this example, we need to calculate the number of bonding electrons in the carbon dioxide molecule. So we need to draw out our Lewis structure to figure this out. And so we should recall that our first step before we draw our Lewis structure is to calculate the total valence electrons in our carbon dioxide molecule. So for every atom beginning with carbon we would recognize on our product table, carbon is located in Group four A. And so we have one carbon atom Multiplied by the four valence electrons, which corresponds to the group number of carbon on the periodic table. And so we have four valence electrons because carbon is in group four a. Moving on to our two oxygen atoms, We're going to multiply this by oxygen which is located in group six a of our periodic table corresponding to six valence electrons that we multiply by. And so adding this together, we would see that we get a total of 16 valence electrons for our Lewis structure. So based on our molecular formula for carbon dioxide, we can see that we have just one carbon atom, which is likely going to be our central atom surrounded by two oxygen atoms. And we're going to begin by recalling bonding preference. And if we think of the bonding preference Of carbon, we would recall that carbon prefers to have four bonds. But if we think of the bonding preference of oxygen, we would recall that oxygen prefers to have two bonds and two lone pairs. And so we can easily make our lowest structure by giving each oxygen to bonds to the carbon. This uses up a total of 2468 of our electrons. So we can say minus eight electrons, which would leave us with eight electrons left and we can use those to fill in our lone pairs on our oxygen atoms. So we would have 12345678. And it is easy to see that each of our atoms are happy because they are bonded according to their preference. So they have a formal charge of zero, meaning we have a stable structure. And we can answer this question by recognizing that each bond contains two electrons. So we would have a total of 2468 bonding electrons. So we can say we have eight bonding electrons because we recognize again that each bond has two electrons which represents each valence electron contributed to that atom it's directly attached to. So this would be our final answer to complete this example corresponding to choice D in the multiple choice I hope that everything I reviewed was clear. If you have any questions, please leave them down below and I'll see everyone in the next practice video