I need help w/ my hw problems
Lindsey A.
and pi covalent bonds?
a. Fe(OH)3 b. HClO c. H2S d. NO2 e. NaCN
2) As the temperature is raised from 20'C to 40'C, the kinetic energy
of neon atoms changes by a factor of
a. 1/2 b. square root of 313/293 c. 313/293 d. 2 e. 4
Bob
wrote:
You get the best help when you show what you have done so far, so we
can focus on where you are stuck.
>1) Which of the following compounds is ionic and contains both sigma
>and pi covalent bonds?
>a. Fe(OH)3 b. HClO c. H2S d. NO2 e. NaCN
>
So do it stepwise. Which are ionic? Then look at those more closely,
to see which have pi bonds. (I suppose you could do it in either
order, but I suspect sorting out the ionic ones first is easier for
most people.)
>2) As the temperature is raised from 20'C to 40'C, the kinetic energy
>of neon atoms changes by a factor of
>a. 1/2 b. square root of 313/293 c. 313/293 d. 2 e. 4
The basic relation between KE and T is ??
bob
Lindsey A.
and that's why I'm stuck here.
For the second question, how do you calculate the kinetic energy of an
element?
Henry Boyter
The second is just an equation for kinetic energy.
You should ask you teacher for extra help on Monday.
--
Henry Boyter, Jr.
PhD Chemist
http://www.itt.edu/staff/boyter/links/index.html
The opinions expressed are those of Dr. Boyter and
are provided for informational purposes only and
should not be used as advice. No warranty or
expression of professionalism is implied.
"Lindsey A." <Linds...@gmail.com> wrote in message
news:1141617632.1...@p10g2000cwp.googlegroups.com...
Lindsey A.
and searched and I can't find the answers.
1) Which of the following compounds is ionic and contains both sigma
and pi covalent bonds?
a. Fe(OH)3 b. HClO c. H2S d. NO2 e. NaCN
2) As the temperature is raised from 20'C to 40'C, the kinetic energy
dlzc1 D:cox T:net@nospam.com N:dlzc D:aol T:com (dlzc)
"Lindsey A." <Linds...@gmail.com> wrote in message
news:1141620151.4...@u72g2000cwu.googlegroups.com...
> Could someone please tell me the answers
> to the problems?
This newsgroup is not "please.do.my.homework.for.me". You have
been given pointers to how to answer it yourself, using materials
you have at hand.
Will you ask your future boss to solve your problems for you? Or
only give you problems you already have been given answers to?
You may feel "up against the wall", but study groups are a good
way to fix this. As is starting before Sunday night.
David A. Smith
Bob
wrote:
>Well, I don't know or understand what sigma and pi covalent bonds are
Ok, that is something specific we can address. (But I am somewhat
surprised you have a question on sigma/pi bonds if they haven't come
up.)
Sigma bonds are "ordinary" simple bonds, such as those in water or
methane.
Pi bonds are involved in double and triple bonds. They are due to
sideways overlap of p orbitals (but you don't need to understand that
to be able to deal with them at a simple level).
As a useful simple guide... If you draw ordinary Lewis structures (say
for the anions in the ionic compounds)... single bonds are sigma.
Double and triple bonds contain one sigma bond plus 1 or 2 pi bonds.
That level of description is sufficient for the question at hand.
>and that's why I'm stuck here.
>
>For the second question, how do you calculate the kinetic energy of an
>element?
No need to calculate. The question is about a relationship, which is
really a conceptual point. It should be introduced along with gas
laws, though might be elsewhere. Try index entries in your book for
both kinetic energy and for temperature.
Note that the possible answers deal with at least two effects. One is
the proper T scale, and another is the power (exponent) in the
relationship. For the former, you should know it from general
principles.
bob
Lindsey A.
Richard Schultz
: On 5 Mar 2006 20:00:32 -0800, "Lindsey A." <Linds...@gmail.com>
: wrote:
: Pi bonds are involved in double and triple bonds. They are due to
: sideways overlap of p orbitals (but you don't need to understand that
: to be able to deal with them at a simple level).
("wrong" is the more precise term), but sufficiently useful for a
high school or freshman chemistry student as long as he is told that it
is a gross oversimplification. I know this because when I teach seniors
about backbonding, at least half of them are either shocked or completely
befuddled when I point out that a d orbital can create a sigma bond or
a pi bond or both. (Or a delta bond, although that usually appears in
a problem set.) This isn't intended to diss you, but to raise a point that
I have found as a teacher of an advanced course: if you teach something
incorrect in an elementary course, the odds that it will stick in the
students' minds to the point of being impossible to remove is roughly
proportional to how incorrect the original concept was.
-----
Richard Schultz sch...@mail.biu.ac.il
Department of Chemistry, Bar-Ilan University, Ramat-Gan, Israel
Opinions expressed are mine alone, and not those of Bar-Ilan University
-----
"an optimist is a guy/ that has never had/ much experience"
Richard Schultz
: Could someone please tell me the answers to the problems? I searched
: and searched and I can't find the answers.
Lloyd Parker
Bob
(Richard Schultz) wrote:
>In article <a2gn02tnctdm5kknj...@4ax.com>, Bob <bbx...@excite.xxxx.com> wrote:
>: On 5 Mar 2006 20:00:32 -0800, "Lindsey A." <Linds...@gmail.com>
>: wrote:
>
>: Pi bonds are involved in double and triple bonds. They are due to
>: sideways overlap of p orbitals (but you don't need to understand that
>: to be able to deal with them at a simple level).
>
>I hope that you realize that this description is incomplete at best
>("wrong" is the more precise term), but sufficiently useful for a
>high school or freshman chemistry student as long as he is told that it
>is a gross oversimplification.
Which is what I said. I think it is important to address questions at
a level appropriate to the person who asked them. In this case, the
idea was to provide some guidance to a student who had at least
bothered to come back and better specify the concern, without doing
the work for them.
>I know this because when I teach seniors
>about backbonding, at least half of them are either shocked or completely
>befuddled when I point out that a d orbital can create a sigma bond or
>a pi bond or both. (Or a delta bond, although that usually appears in
>a problem set.) This isn't intended to diss you, but to raise a point that
>I have found as a teacher of an advanced course: if you teach something
>incorrect in an elementary course, the odds that it will stick in the
>students' minds to the point of being impossible to remove is roughly
>proportional to how incorrect the original concept was.
>
What is it that concerns you? That is, what simplification that is
being taught early is causing you a problem later on?
If your concern is that I did not say that p orbitals can form either
type of bond, that is simply because that wasn't relevant in this
case. (If possible, let's avoid d orbitals here, as their bonding is
usually mentioned little if at all at the level of the student here.)
The general problem of the risks of simplifications is of concern, as
you suggest. Sometimes you just need to address it head-on, by saying
something to the effect... Some of you may have learned ... That is a
useful simplification in the beginning, but now we need to go beyond
that, and see its limitations, and use a more complete model.
But in this case, I can't tell what your concern is.
bob