Fundamentals of Chemistry Question Thread (VCE-level chem)

[hobbitle]

Haha you don't have to flatter the tutors mate! There are some really crap ones.

[hobbitle]

I just had my tute and it also was confusing on that point. They said that homog was "matter of a single phase" and heterogeneous was "matter of a mixture of phases" which makes sense sort of but I don't feel like it's always true.
Like you could have a mixture of sand and marbles and they are both solids but they still don't mix to become homogeneous.

[hobbitle]

She also said atmosphere was heterogeneous because of dust particles and stuff which I understand where she's coming from but I'm pretty sure that's a misleading answer.

[PlainElegy]

Too bad...who is your tutor? I have got a lady too as a tutor...can't be too sure about what her name was...and she happily told the tute class that she would be with us for the whole semester...

I think we might have the same tutors because what you talked about was similar to what I experienced.

[hobbitle]

I think we might have the same tutors because what you talked about was similar to what I experienced.

I had a lady with short blonde hair, Sonia.  She said she was leaving us after a few weeks and we would get Mick once he had finished his lecture series (hooray, I like him).  It seems like such a petty thing to be having a dispute about but I did try to ask her about it in class and she just got totally vague and didn't answer properly so I had to email Mick with quotes from Zumdahl text.  Makes me feel so petty having to do that crap but honestly I just want a straight answer.

[PlainElegy]

Yep, I have the same tutor

[PlainElegy]

Don't know whether anyone's is still viewing this thread, but if you are reading this....

Are all orbitals filled from lowest to highest in order? Or do different elements have different suborbitals being filled to the maximum while others may contain like three electrons instead of 6 electrons? I'm rather confused...the textbook ain't helping.

[hobbitle]

Are all orbitals filled from lowest to highest in order? Or do different elements have different suborbitals being filled to the maximum while others may contain like three electrons instead of 6 electrons? I'm rather confused...the textbook ain't helping.

When you make a new post the thread goes back to the top of the list and appear under 'unread posts'.

I'm not quite sure how to interpret your question.

First some terminology: atoms have SHELLS, SUBSHELLS, and ORBITALS (no suborbitals... at least, if there are, we haven't been taught that they exist).

Basically, all elements generally speaking fill their orbitals in the same order (the order dictated by the Aufbau diagram from the lecture notes).

Assuming the atom is in a neutral and ground state, it will always have the same electron configuration.

Different elements have different valence electrons, that is - different numbers of electrons in their outer shell.

So you can use the Aufbau diagram (I do it differently but thats what they've been using in tutes so let's stick with that) to determine the electron configuration of a given atom.  Let's do, say, calcium (Ca atomic number 20):

1s² 2s² 2p⁶ 3s² 3p⁶ 4s²

The large numbers represent the SHELL, the letters represent the SUBSHELL and the superscript numbers represent the number of electrons in that subshell (instead of saying 2p6 we could say 2p_x² 2p_y² 2p_z² but that's just tedious).  The largest SHELL number here is 4, and there are 2 electrons in that shell, so Ca has 2 valence electrons.

Sorry I'm probably not really answering your question but I'm just struggling to figure out what you mean.  Yes, orbitals fill from lowest to highest energy.  Some elements have full orbitals and subshells when they are in ground/neutral state, some don't.  Carbon has 2 electrons in its 2p subshell, Nitrogen has 3 electrons in its 2p subshell, Oxygen has 4 electrons in its 2p subshell.  In Neon atoms, the 2p subshell is full.

[hobbitle]

Here is a super dorky but actually really effective way of learning that slide (from Lecture 6) of polyatomic molecules and their charges:
http://www.wimp.com/polyatomicions/

[PlainElegy]

TY! Really much gratitude for your effort and time spent in writing out this stuff!