c. Why are Group 1A (1) and Group 2A (2) elements found in many c...

Question

c. Why are Group 1A (1) and Group 2A (2) elements found in many compounds, but not Group 8A (18) elements?

Accepted Answer

Welcome back, everyone. We need to identify the correct explanation for why compounds of group one A and group two A elements are more abundant compared with that of group eight A elements. Choice A states that because group eight A elements are normally unreactive due to their completely unfilled outer shells. While group one A and the group two A elements have partially filled outer shells and only need to gain electrons to form compounds. Choice B states that group eight A elements are normally unreactive since they're gasses. And while group one A and group two A elements are reactive since they are solids. Choice C states that group A A elements are normally unreactive due to their completely filled outer shells. While group one A and the group two A elements are reactive and would only need to gain electrons to form compounds. And choice D states that group A A elements are normally unreactive due to their completely filled outer shells. While group one A and group two elements are reactive and would only need to lose electrons to form compounds. So let's begin by recalling our trend on our periodic tables for electron negativity which increases in the direction of fluorine. So towards the top right of our periodic table. So again, this is increasing electro negativity based on this trend recall that group one A and group two A are towards the left of our periodic table. And right most to the periodic table, we have group eight A where we would understand that our atoms in group eight A are going to be highly electron negative and our atoms in group one A and two A are going to be much less electron negative. And due to that low electron negativity, we would understand that elements in group one A and two A will have more energetic favorability towards losing electrons and forming cat ions. And so in choice A where it states that group one A and two A have partially filled outer shells. We would agree with that, but it says that they only need to gain electrons to form compounds. We would disagree with that because as we stated, based on the low electron negativity group one A and two A elements will want to lose electrons in choice A, it also states that group eight A elements are normally unreactive due to their completely unfilled outer shells. And the outer shell is in reference to our valence shell. We want to recall that because group 8 a actually has a full valence shell, they're going to be pretty reactive. So we would correct this to say full or filled outer shells for group 8 a. So so far, we would rule out choice A and looking at choice C which again states that group one A and group two A elements only need to gain electrons to form compounds. We would correct this to say lose electrons. So we would still rule out choice C as well. This leaves us between choice B and D. Looking at Choice B recall that group A A represents our noble gas group on our periodic table. So in Choice B, it states that group A A elements are normally unreactive since they are gasses. While group one A and group two A elements are reactive since they are solids. Now, even though Choice B is an accurate statement, whether our elements are solids or gasses is not relevant, especially towards the abundance of these elements as far as our group one A and group two A elements. So as long as our substance is not inert this information and Choice B is not relevant to explaining the abundance of group one A and two A elements in comparison to our noble gas group. So we would rule out Choice B, this leaves us with choice D which states again that group A A elements are normally unreactive due to their completely filled outer shells. While group one A and group two A elements are reactive and would only need to lose electrons to form compounds. And based on what we outlined for electron negativity of being sorry, the low elect negativity of group one A and group two A elements that would make them have a higher energetic favorability towards losing electrons and forming ions in order to form compounds. And so choice D is definitely an accurate explanation. And we would confirm choice D as our final choice to explain why group one A and group two A elements are more abundant than group eight A elements. I hope that this makes sense and let us know if you have any questions.

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c. Why are Group 1A (1) and Group 2A (2) elements found in many compounds, but not Group 8A (18) elements?

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