Give the ground state electron configuration and number of unpaired electrons in a Ru2+ ion. (LO 6.1, 6.2) (a) 3Kr45s2 4d4 0 unpaired electrons (b) 3Kr45s2 4d6 0 unpaired electrons (c) 3Kr44d6 4 unpaired electrons (d) 3Kr45s24d4 4 unpaired electrons

Video transcript

Hello everyone today. We have the following problem. Please provide the electron configuration of the ground state. And the number of electrons that are not paired in a tech medium, four plus ion. So the first thing you want to recall is that when we have a neutral atom meaning there are no charges, the number of protons is equal to the number of electrons. And both of these are going to be equal to the atomic number. And so if you take a neutral tech needy um out of them, The atomic number is gonna be 43 and therefore it's going to have 43 protons and 43 electrons. And so now we have to to write the condensed formula here. So to write the condensed electron configuration, we first must look at the preceding noble gas. So what noble gas comes directly before tech needy. Um, and if we observe, we see that this is going to be Krypton or KR for short. And so we're going to write our noble gas and brackets, followed by what the electrons would be after. We have krypton. So we're gonna be in the fifth period, which means we're gonna start off with our five, we're gonna start with our five orbital filling those first two and then tech needy um, is going to be the fifth element in the four D orbital. So what does that look like? We're gonna have our four D five as the exponent. And so this is going to be our condensed electron configuration here for neutral tech medium. So we're gonna keep that in the back of our mind. We then must take notice of this four plus ion that's in the question. So this plus four means that four electrons were removed. Remember positive charges of the opposite of negative charges and negative charges denotes electrons. So four electrons were removed from neutral tech needy. Um and so we have to determine where we're going to take those electrons from. So we remove electrons from the highest orbital first and out of our five s orbital's and R four D orbital's. That's going to be our four D. So when we write out our electron configuration for tech medium four plus, we're still gonna have our noble gas in our brackets and we're gonna have our five S two. And instead of 45 we remove four electrons. That's going to turn into four D one. So this is going to be our condensed formula for this tech needy um 4-plus ion. And so how do we determine which electrons are impaired? We have to simply draw the orbital diagram. So when we draw the orbital diagram for our condensed formula here, we have our krypton followed by our five s orbital which can hold a maximum of two electrons in our four D orbital That can hold a maximum of 10 electrons. So as we have here, the exponents are going to be for electrons. So for five s we have our two arrows. And so we have our two electrons fill for the five S orbital, and then for our four D, we only have one. So essentially the number of electrons that are UNP aired is one, so we have one UNP aired electron by itself. And so this is going to be the complete answer for this question. Overall, I hope that this helped, and until next time.