Some chemistry questions

Pre-College Issues High School Life
1

<p>THIS IS NOT HOMEWORK HELP!!!</p>

<p>Okay, so I have to read this chapter. But I totally don't understand whatever the book is saying. So here are several questions I have: (We are on the Chemical periodicity, trends and all that)</p>

<p>1) So the book says, "the group equals number of electrons in the outermost energy level," meaning group 4A should have 4 electrons in its outermost energy level, right?
but the configuration of Carbon is : 1s2 2s2 2p2
There are only 2 at the outermost level? Or does the book means the outermost level[bold]s[/bold]</p>

<p>2) The book says, "each period number correspond to the principal energy level. The number of electrons in each sublevel is determined by counting over to the element from left to right. For the transition elements, electrons are added to a d sublevel with a principal energy level that is one less than the period number."</p>

<p>Question: What does all that mean? So if the period number is 7, how do you determine the number electrons in each sublevel; s, p, d ,f?
What does the last sentence mean? </p>

<p>3) Oh, and if anyone's willing, please explain to me what the pseudo noble gas configuration is.</p>

<p>I'm struggling in Chemistry. And these questions are what I'm confused about. Please help me, thank you.</p>

2

<p>The first rule of CC is… <a href=“http://talk.collegeconfidential.com/high-school-life/452903-no-homework-help-posts-allowed-cc.html[/url]”>http://talk.collegeconfidential.com/high-school-life/452903-no-homework-help-posts-allowed-cc.html&lt;/a&gt;&lt;/p&gt;

3

<p>gosh. did you read the first line? this is not homework help. I’m reading the chapter, not as homework, but to get a head start into what the teacher is going to teach.</p>

4

<p>^ I read the first line which claims that it is not homework help… but the rest of it does read a lot like homework help.</p>

<p>Without trying to say too much… Carbon DOES have 4 electrons in it’s outer shell, because the 2s and 2p are both part of the second orbital.</p>

<p>As for the d-orbitals question, the 3d subshell has a higher energy level than that of the 4s subshell (same applies for 4d and 5s etc).</p>

<p>I do not know what exactly you mean by pesudo-noble gas configuration but I think it means writing out something like this</p>

<p>V = [Ar]3d3 4s2</p>

5

<p>Thank you
so how do you define a shell? What does it consist of? all s,p,d,f? I always mix it up with the “orbital”. But doesn’t the book say the outermost energy level? Does it refer to shell or orbital?</p>

6

<p>Subshell refers to something like 2s or 3d or really any number-letter combo</p>

<p>Subshells contain orbitals (s has one, p has 3, d has 5, f has 7 IIRC). Each orbital can hold two electrons, one “up” one “down”</p>