Chemistry 2006/ 2007 Club***

stacyinMD · Feb 10, 2006

This is the BEST Chemistry site I have found on the internet. It's aimed toward high school chemistry, but it has been such an asset for me. http://dbhs.wvusd.k12.ca.us/webdocs/ChemTeamIndex.html

Thanks so much for this link! I forwarded to the students in my chem class. Very helpful!

Stacy

maliat · Feb 10, 2006

Hi Everyone, hope your semester is off to a great start. I'm fortunate enough to have two professors who seem approachable if I need help.
I have a question I forgot to ask before leaving class last night....does anyone know how to do subscripts using microsoft word? I'm trying to type my lab report and I can't remember how to do this.
Thanks so much!!!
Stacy

Select the number you want to change, then go to Format, then select font. Under effects you'll see subscript.

I hope this helps.

Malia

stacyinMD · Feb 10, 2006

Select the number you want to change, then go to Format, then select font. Under effects you'll see subscript.
I hope this helps.
Malia

Thanks so much Malia! I tried your trick...I had to use superscript for scientific notation.

Stacy

MJJFan1, BSN, RN · Feb 12, 2006

I UNDERSTAND IT!!!!!!! I was having trouble with Stoichiometry, I was actually contemplating dropping the class-that's how much I didn't understand it- but guess what? 20 minutes of help from my husband and I have it all down. I can't go wrong. I can't believe how easy it is.

droopy1592 · Feb 16, 2006

I'm new here but really good in chemistry... If you have any questions you can PM me and I can try to help you.

JeanettePNP, MSN, RN, NP · Feb 16, 2006

Chemistry question: Can anyone explain why atomic radii get smaller as you go across the Periodic Table (with increasing number of electrons), but ionic radii get bigger the more electrons they have? The explanations given for the two seem contradictory - the atomic radius gets smaller because the greater number of electrons create a bigger charge getting pulled towards the nucleus. In ions, the extra electrons are less attracted to the nucleus so the radius is bigger.

casi, ASN, RN · Feb 17, 2006

As you go across the the nuclear charge increases (#protons-# core electrons) causing a stronger pull on outter electrons pulling them in closer to the nucleus. So the closer to having the outter valence full the closer the outter electrons are pulled to the nucleus.

As you go down the periodic table radii get bigger due to additional more electron shells. The more electron shells the less attraction, but the closer to filling the valence shell the more attraction.

I don't think I'm making any sense. Sorry.

JeanettePNP, MSN, RN, NP · Feb 17, 2006

I think I'm getting it.

More protons = more attraction to the nucleus

More electron shells - more shielding effect, less attraction to the nucleus

Additional electrons (ions) - less attraction to the nucleus

beepeadoo · Feb 17, 2006

I think I'm getting it.
More protons = more attraction to the nucleus
More electron shells - more shielding effect, less attraction to the nucleus
Additional electrons (ions) - less attraction to the nucleus

You got it exactly!

droopy1592 · Feb 17, 2006

Good explanation

andrea5 · Feb 19, 2006

I'm am so stuck, please can anyone help me with this q

A sample of neon gas occupies a volume of 23.4L at STP. What volume, in liters, will it occupy at a pressure of 0.750 atm and a temp of -20 C?

br107 · Feb 19, 2006

The question is asking you to compare 2 situations.

First look at what your'e given...

P1 = STP = 1.00 atm

V1 = 23.4L

T1 = STP = 273K

P2 = 0.750 atm

V2 = ???L

T2 = -20.0C = 253K

Considering the givens, we should compare relationships using the combined gas law:

(P1V1)/T1 = (P2V2)/T2

I prefer algebra. So solving algebraically,

V2 = (T2)*(P1V1)/(T1/P2) =

1.00atm * 23.4L * 253K

------------------------

0.750atm * 273k

= 28.9L

NOW FOR WHY I'M HERE....anyone got good websites for organic or biochem?