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A simple chemistry question...

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chutsu

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Dec 26, 2009, 7:10:16 PM12/26/09
to
I know this is a physics newsgroup, but should be able to answer this
question anyways.

My question is, why are all atoms neutral? Apart from it has equal
amounts of electrons and protons.. like why or how do we know that
atoms in the periodic table is neutral?

Thanks

Sam Wormley

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Dec 26, 2009, 7:37:13 PM12/26/09
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They aren't. Most of the atoms in stars are stripped of electrons.
The electromagnetic force is very strong and tends to make low
energy atoms neutrally balanced charge-wise.

Google is your friend
http://en.wikipedia.org/wiki/Atom#Electron_cloud


Javi

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Dec 26, 2009, 8:23:53 PM12/26/09
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chutsu wrote:

There are many situations where atoms aren't neutral, but are ionizied.
Atoms tend to be neutral because if there is a net electric charge, it will
tend to attract the same amount of electrical charge of the opposite sign.

Uncle Al

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Dec 26, 2009, 10:21:20 PM12/26/09
to
chutsu wrote:
>
> I know this is a physics newsgroup, but should be able to answer this
> question anyways.

The approach ramp needs tiger striping.

> My question is, why are all atoms neutral?

External charge arrives in integral packets only. Equal numbers of
nuclear protons and orbiting electrons. You could take some high
school chemistry or, gasp!, read a book.

> Apart from it has equal
> amounts of electrons and protons.. like why or how do we know that
> atoms in the periodic table is neutral?

Pith ball on a thin tether, a few excess or deficient electrons. A
charged lump is detectable. Mass spec for individual atoms.
Batteries work to spec - no surprises. Field effect transistors work
- no surprises. Little at Stanford looking for fractional charges,
Millikin and his oil drops. No surprises.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz4.htm

alie...@gmail.com

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Dec 26, 2009, 10:56:57 PM12/26/09
to
On Dec 26, 7:21 pm, Uncle Al <Uncle...@hate.spam.net> wrote:
> chutsu wrote:
>
> > I know this is a physics  newsgroup, but should be able to answer this
> > question anyways.
>
> The approach ramp needs tiger striping.

Some days I think it needs IFF and ack-ack.


Mark L. Fergerson

chutsu

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Dec 27, 2009, 9:06:28 AM12/27/09
to
On Dec 27, 3:21 am, Uncle Al <Uncle...@hate.spam.net> wrote:
> chutsu wrote:
>
> > I know this is a physics  newsgroup, but should be able to answer this
> > question anyways.
>
> The approach ramp needs tiger striping.
>
> > My question is, why are all atoms neutral?
>
> External charge arrives in integral packets only.  Equal numbers of
> nuclear protons and orbiting electrons.  You could take some high
> school chemistry or, gasp!, read a book.
>

I did read a book! According to "Chemistry for the Biosciences By
Jonathan Crowe" on page 10, it says "Protons and Electrons always bear
an electrical charge" Fair enough, "all atoms are uncharged." <---
meaning its neutral, I was merely trying to understand why does the
book assume that all atoms are uncharged, cause I know they usually
aren't in real life.

> > Apart from it has equal
> > amounts of electrons and protons.. like why or how do we know that
> > atoms in the periodic table is neutral?
>
> Pith ball on a thin tether, a few excess or deficient electrons.  A
> charged lump is detectable.  Mass spec for individual atoms.
> Batteries work to spec - no surprises.  Field effect transistors work
> - no surprises.  Little at Stanford looking for fractional charges,
> Millikin and his oil drops.  No surprises.

I thought Millikan's Oil drop experiment was to measure the electric
charge of an electron. What has this got to do with atoms being
neutral?
> --
> Uncle Alhttp://www.mazepath.com/uncleal/

Androcles

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Dec 27, 2009, 9:24:10 AM12/27/09
to

"chutsu" <chu...@gmail.com> wrote in message
news:1013f251-408b-4ebe...@a6g2000yqm.googlegroups.com...

On Dec 27, 3:21 am, Uncle Al <Uncle...@hate.spam.net> wrote:
> chutsu wrote:
>
> > I know this is a physics newsgroup, but should be able to answer this
> > question anyways.
>
> The approach ramp needs tiger striping.
>
> > My question is, why are all atoms neutral?
>
> External charge arrives in integral packets only. Equal numbers of
> nuclear protons and orbiting electrons. You could take some high
> school chemistry or, gasp!, read a book.
>

I did read a book! According to "Chemistry for the Biosciences By
Jonathan Crowe" on page 10, it says "Protons and Electrons always bear
an electrical charge" Fair enough, "all atoms are uncharged." <---
meaning its neutral, I was merely trying to understand why does the
book assume that all atoms are uncharged, cause I know they usually
aren't in real life.

==============================================
The positive charge is in the middle, the negative charge is on the
outside. You'll meet the negative charge first, but atoms are "uncharged"
in the sense that the electrons balance the protons of the nucleus
to give a sum of zero charge.

Edward Green

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Dec 27, 2009, 11:46:42 AM12/27/09
to

Obviously all of these systems have failed for some time. Still, did
you check out the cross posted clip about paranoid schizophrenics?
That was hilarious. I wonder if there are really 1.5 million
_diagnosed_ paranoid schizophrenics in the US. Imagine a medium sized
city populated by nothing by paranoid schizophrenics. That's
frightening.

alie...@gmail.com

unread,
Dec 27, 2009, 7:34:43 PM12/27/09
to
On Dec 27, 8:46 am, Edward Green <spamspamsp...@netzero.com> wrote:
> On Dec 26, 10:56 pm, "n...@bid.nes" <alien8...@gmail.com> wrote:
>
> > On Dec 26, 7:21 pm, Uncle Al <Uncle...@hate.spam.net> wrote:
>
> > > chutsu wrote:
>
> > > > I know this is a physics  newsgroup, but should be able to answer this
> > > > question anyways.
>
> > > The approach ramp needs tiger striping.
>
> >   Some days I think it needs IFF and ack-ack.
>
> Obviously all of these systems have failed for some time.  Still, did
> you check out the cross posted clip about paranoid schizophrenics?

Not until you pointed me to it; thanks.

> That was hilarious.  I wonder if there are really 1.5 million
> _diagnosed_ paranoid schizophrenics in the US.  Imagine a medium sized
> city populated by nothing by paranoid schizophrenics.  That's
> frightening.

I thought it very funny too. Well, a city of schizos could follow
each other around and compare voices I suppose... but then I think
about the borderline cases that see that video and take it seriously.

I think I told you about how, some years ago, I investigated the
Hieronymus machine (with negative results).

My roomie-at-the-time's sister asked me what I was building, so I
innocently babbled on about its alleged capabilities. I told her I
though it was all BS but wanted to find out for myself.

Couple days later I find she had been hospitalized after going full-
blown fuckobazoo about how I was reading her mind and putting
"thoughts" into her head, the government was after her, yada yada.

She's out living her life, on meds, and hasn't spoken to me since.

On the one hand, the whackos on the newsgroups can be fun to play
with, but on the other hand, how many of them are that close to losing
it?


Mark L. Fergerson

hhc...@yahoo.com

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Dec 28, 2009, 3:29:43 AM12/28/09
to

Sam, not to be pedantic, but an atom stripped of an electron or with
an added electron is an "Ion", an atom with a polarity..

All atoms are electrically neutral to fit the definition of an atom.
For the original poster an alpha particle is a helium nucleus,not an
atom.
Similarly, a proton is a hydrogen nucleus, not an atom.

You can put an electrical charge on an aluminum pan, but that does't
alter its atomic structure...it's still aluminum.

Harry C.

.

Sam Wormley

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Dec 28, 2009, 8:55:48 AM12/28/09
to

Thanks Harry, I agree. However, astronomers identify
their atoms by the spectral lines, and seldom add the
word "ion".

Sam Wormley

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Dec 28, 2009, 9:15:14 AM12/28/09
to

Actually to be fair, astronomers seldom use the word "atoms"
referring instead to element names... Hydrogen, Iron, Potassium,
etc.

Uncle Al

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Dec 28, 2009, 12:27:14 PM12/28/09
to
chutsu wrote:
>
> On Dec 27, 3:21 am, Uncle Al <Uncle...@hate.spam.net> wrote:
> > chutsu wrote:
> >
> > > I know this is a physics newsgroup, but should be able to answer this
> > > question anyways.
> >
> > The approach ramp needs tiger striping.
> >
> > > My question is, why are all atoms neutral?
> >
> > External charge arrives in integral packets only. Equal numbers of
> > nuclear protons and orbiting electrons. You could take some high
> > school chemistry or, gasp!, read a book.
> >
>
> I did read a book! According to "Chemistry for the Biosciences By
> Jonathan Crowe" on page 10, it says "Protons and Electrons always bear
> an electrical charge" Fair enough, "all atoms are uncharged." <---
> meaning its neutral, I was merely trying to understand why does the
> book assume that all atoms are uncharged, cause I know they usually
> aren't in real life.

"Chemistry for the Biosciences" giggle

Sodium chloride. Are any of those atoms charged?

> > > Apart from it has equal
> > > amounts of electrons and protons.. like why or how do we know that
> > > atoms in the periodic table is neutral?
> >
> > Pith ball on a thin tether, a few excess or deficient electrons. A
> > charged lump is detectable. Mass spec for individual atoms.
> > Batteries work to spec - no surprises. Field effect transistors work
> > - no surprises. Little at Stanford looking for fractional charges,
> > Millikin and his oil drops. No surprises.
>
> I thought Millikan's Oil drop experiment was to measure the electric
> charge of an electron. What has this got to do with atoms being
> neutral?

Where was the extra electron?


--
Uncle Al

Androcles

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Dec 28, 2009, 3:00:40 PM12/28/09
to

"Uncle Al" <Uncl...@hate.spam.net> wrote in message
news:4B38EA71...@hate.spam.net...
[snip crap]
Idiot.
[snip more crap]
Bigot.
[snip yet more crap]
Arsehole.


hhc...@yahoo.com

unread,
Dec 30, 2009, 12:03:11 AM12/30/09
to
>    word "ion".- Hide quoted text -
>
> - Show quoted text -

Sam, quite true, but that is not the question that the OP asked.

Again, not to be pedantic, but spectral lines are the characteristics
of elements, not atoms. They amount to the same thing, with an
important difference. Spectral lines are associated with the excited
nucleus of an element, and incorrectly sometimes called atomic
spectra. The atomic spectra has nothing to do with the electrons that
surround an atom and render it neutral. They are entirely based on the
nucleus of the atom itself.

I remember this because as an undergraduate I did my research project
in optical emission spectography. This is rather dated technology
today, but it provides a foundation for more advanced work.

The experimental procedure here is to "burn" a sample of some material
in a spectrographic arc (simply 2 sticks of carbon with a cavity to
hold a sample). The electric arc removes the electron layers in a
fraction of a second, and what remains giving off electromagnetic
radiation is the nucleus of the atom, not the atom itself. This
electromagnetic radiation (bright line specta or atomic spectra) is
passed through either a prism or grating and recorded on a
photographic plate. On analysis, the lines on the plate reveal the
identity of the element that produced them.

What I did not mention is that in spectrographic analysis, a sample of
iron is usually burned first, since the what are called the critical
lines of the iron spectra are well known and documented. Then, the
photographic plate is indexed upward and the sample is burned. This
permits comparison of the spectral lines of the sample to be compared
with those of iron, which serves as a yardstick, so the lines in the
sample can be compared with those of iron and, once known, can be
looked up in a book called the International Critical Tables.

Astronomers use precisely the same method, plus a little trial and
error in their calibrations.

Remember, I am recalling all of this from around 1957, but it should
be close enough for government work.

Harry C.

Sam Wormley

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Dec 30, 2009, 9:23:14 AM12/30/09
to

Thanks Harry!
-Sam

Y.Porat

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Dec 30, 2009, 9:41:05 AM12/30/09
to

seems right
but still alot to learn:

no existing theory can explain
the complete spectrum of a heavy Atom!
certianly not if it is based on
'the number of protons in the nuc= equal to the number of electrons
'around it' !!
2
see the 'chain of orbitals idea:

it is about the connection between
heavy orbitals (of the nuc mediating orbitals )and lighter orbitals -
the electrons
all of them connected in one * linear chain *

ATB
Y.Porat
-----------------------


PD

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Dec 30, 2009, 6:42:30 PM12/30/09
to

They're not. Ones that have an imbalance between electrons and protons
are called ions.
However, in the process of these objects interacting with other
objects, it is often the case that the excess charge is taken off
(because the electromagnetic interaction is pretty strong), leaving a
neutral product.

Edward Green

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Jan 1, 2010, 12:21:09 PM1/1/10
to

Obviously, But that does raise an interesting question: does charging
an aluminum pan alter its chemistry? For example, is a negatively
charged pan slightly more electronegative than neutral aluminum,
hence, have a slightly lower ignition temperature in air, for example?

Edward Green

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Jan 1, 2010, 12:35:31 PM1/1/10
to
On Dec 27 2009, 7:34 pm, "n...@bid.nes" <alien8...@gmail.com> wrote:

>   I thought it very funny too. Well, a city of schizos could follow
> each other around and compare voices I suppose... but then I think
> about the borderline cases that see that video and take it seriously.

It was very well done.

>   I think I told you about how, some years ago, I investigated the
> Hieronymus machine (with negative results).
>
>   My roomie-at-the-time's sister asked me what I was building, so I
> innocently babbled on about its alleged capabilities. I told her I
> though it was all BS but wanted to find out for myself.
>
>   Couple days later I find she had been hospitalized after going full-
> blown fuckobazoo about how I was reading her mind and putting
> "thoughts" into her head, the government was after her, yada yada.
>
>   She's out living her life, on meds, and hasn't spoken to me since.
>
>   On the one hand, the whackos on the newsgroups can be fun to play
> with, but on the other hand, how many of them are that close to losing
> it?

Thanks for getting me to look up "Hieronymus machine".

At least your ex-roomie's sister is on meds. Interesting story.

Uncle Al

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Jan 1, 2010, 3:47:57 PM1/1/10
to


Wyy do you bolt blocks of zinc to your iron boat hull or bridge?

jmfbahciv

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Jan 2, 2010, 8:27:23 AM1/2/10
to

I've been told that you also have to be very careful about how
you ground your electrical system on a boat.

/BAH

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