Thread: Chemistry questions

Biology is a science, though the way it is taught in many schools, it barely qualifies. A lot of the 'school biology' is just memorization, and doesn't really require much actual thinking.

Yeah... Biology is a science. What I meant was that in my haste I chucked a freudian slip and said bio wasn't a science instead of making a direct attack on dumb jocks in my school.

And about the matrix analogy... you just ruined my day.

and about this so called octet rule... what is it?

edit::
And about the electron configurations of elements... I cannot explain why there are inconsistencies in the pattern progression (i forgot specifically which elements break the pattern but e.g. one element wud prolly be like 2,8,13,2 and the next wud be 2,8,15,1 instead of the expected 2,8,14,2.. [these configs are arbitrary] ) Is this a direct consequence of the inane models used in highschools?
Likewise with why transition metals will have inconsistent valencies dependant on what it is reacting with.

and about this so called octet rule... what is it?

It goes something along the lines of: "The reason chemical reactions occur is so that each atom is able to get a full outer shell of electrons". Given that all the "shells" other than the first one supposedly contain 8 electrons its called the octet rule. From your query below it seems that perhaps it has not been emphasised in your course.

And about the electron configurations of elements... I cannot explain why there are inconsistencies in the pattern progression (i forgot specifically which elements break the pattern but e.g. one element wud prolly be like 2,8,13,2 and the next wud be 2,8,15,1 instead of the expected 2,8,14,2.. [these configs are arbitrary] ) Is this a direct consequence of the inane models used in highschools?

I think what you are talking about is the change in energy between the 4s and the 3d which occurs in the transition elements.

Lets take Nickel, its electronic structure is

1s2 2s2 2p6 3s2 3p6 4s0 3d10

Whereas its expected to be 4s2 3d8

Basically the 4s and the 3d are very similar in energy and due to orbital shielding effects the 4s ends up feeling less effective nuclear charge and hence becomes higher in energy than the 3d in certain situations.

So to answer your question, yes its due to inane models, (though I covered this particular topic pre-undergrad) as soon as you start talking about orbitals and their effects on shielding and nuclear charge it make more sense (although you don't start getting any explanations for why orbitals are the way they are untill a much higher level).

Likewise with why transition metals will have inconsistent valencies dependant on what it is reacting with."

The differing valencies of transition metals can't really be understood untill you start covering molecular orbital theory, crystal field theory, and the effects of ligands with regards to stabilising charges.

>> From your query below it seems that perhaps it has not been emphasised in your course

No, my course basically revolves around this principle. Except we don't call it that.

And damn.. i don't understand your electron config notation, with the letters between numbers i feel so primitive. I bet they have something to do with your mentioned modern theories. I am interested in them and would investigate them further but because I am about a year and a half away from my final exams (equivalent to the american SAT or ACT or whatever, the university entrance one) I'm highly preoccupied by all this assorted gibberish they throw at me.

But again, thanks Clyde, you've broadened my understanding a lil, now that I know the stuff I've been learning are all lies.