Chemical Forums

General Forums => Generic Discussion => Topic started by: Mitch on July 01, 2004, 11:58:12 PM

Title: Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: Mitch on July 01, 2004, 11:58:12 PM
Knowing Avogadro's number explain why the sky is blue.

What is the electronegativity of Neon?
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: AWK on July 02, 2004, 09:09:07 AM
Knowing Avogadro's number explain why the sky is blue.
In the night sky is black!
Seriously - there is no correlation

What is the electronegativity of Neon?
Which scale?
See www.weblements.com/webelements/elements/text/Ne/eneg.html
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: jdurg on July 02, 2004, 02:52:22 PM
Knowing Avogadro's number explain why the sky is blue.
In the night sky is black!
Seriously - there is no correlation

What is the electronegativity of Neon?
Which scale?
See www.weblements.com/webelements/elements/text/Ne/eneg.html

Well, you can use Avogadro's Number and the percent composition of air to determine the molar composition of standard air.  From this you can calculate the wavelengths of light absorbed and reflected in our atmosphere and determine which wavelengths are the most visible.  Due to the very high quantity of Nitrogen in our atmosphere, our sky appears to be blue.  During sunset and sunrise, the angle of the sun is close to the horizon where a greater quantity of CO2 exists causing the sky to take on a reddish tinge.  On Mars, the sky is red since its atmosphere is almost entirely carbon dioxide.
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: Mitch on July 03, 2004, 02:20:59 AM
These questions are just some I'm starting to collect. I'm not sure there is any right answer, mostly the committee just wants to see how you begin to approach the problem.
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: today on August 13, 2004, 08:29:50 PM
are you guys PhD students?  ::)
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: ssssss on August 14, 2004, 10:14:09 AM
are you guys PhD students?  ::)

Yeah.Are you peaple phd students?
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: Mitch on August 14, 2004, 06:43:13 PM
Most of the staff are PhD students. But others are lecturers, undergrads and a few high school students.
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: today on August 14, 2004, 08:37:26 PM
Mitch, i can see that you are only 23 and already a PhD student? wow, you must be very smart  :book:
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: Mitch on August 14, 2004, 08:39:34 PM
By the time I actually obtain my PhD I'll be old.
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: jdurg on August 14, 2004, 11:47:43 PM
I am not a PhD student.  I just have a B.S. in Forensic Chemistry and a strong interest in chemistry.  (As can be seen by my collection of elements).  
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: Donaldson Tan on August 15, 2004, 12:22:47 AM
I'm only an engineering undergraduate.
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: today on August 16, 2004, 01:42:30 PM
I am not a PhD student.  I just have a B.S. in Forensic Chemistry and a strong interest in chemistry.  (As can be seen by my collection of elements).  





really?
i find your replies very interesting even if you just have a B.S degree   :coolio:  but why that signature?   :fart2: :censored:
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: jdurg on August 21, 2004, 09:30:21 PM
really?
i find your replies very interesting even if you just have a B.S degree   :coolio:  but why that signature?   :fart2: :censored:

Well, many people have said that I have an "odd" sense of humor and a very unique personality.  My past is riddled with very humorous and sometimes stupid stories.  The quote comes from a website that I frequently visit because it insults and attacks anything and everything.  The quote just made me laugh uncontrollably.  Also, I believe that if you cannot laugh at a fart joke, then you have become old.  The day that I find a fart joke to be not funny is the day that life has passed me by.   ;D
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: ssssss on August 22, 2004, 04:49:00 AM
Well, many people have said that I have an "odd" sense of humor and a very unique personality.  My past is riddled with very humorous and sometimes stupid stories.  The quote comes from a website that I frequently visit because it insults and attacks anything and everything.  The quote just made me laugh uncontrollably.  Also, I believe that if you cannot laugh at a fart joke, then you have become old.  The day that I find a fart joke to be not funny is the day that life has passed me by.   ;D


Very similar to my life.I am a high school passout,preparing for engineering entrance examination.
Title: Re:Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: today on August 24, 2004, 11:10:59 AM
well, as i remember the first time i read it i also laughed, but it was naaasty too ;D
Title: Re: Unusual Questions Asked at Chemistry Qualifying Exams (PhD candidacy)
Post by: ChrisHarding on October 25, 2014, 04:22:31 AM
Knowing Avogadro's number explain why the sky is blue.


Hello,

The question regarding Avogadro's number and the blue sky is actually a fairly famous question from Physical Chemistry.

If I remember correctly, it is an approximation that has to do with the relationship to mole, Standard Temperature and Pressure (STP), the fact that one mole of gas occupies a 22.4 liters at STP, and the distance between the gas molecules as related to wavelength and scattering. A back calculation is pe

As a chemical engineering student taking physical chemistry, this was one question on a test of mine at Oregon State University. If I remember correctly, our question was actually: "By the knowledge that the sky is blue, derive Avogrado's number."

I know this post is old, but I thought I would add my two cents. Actually, I only have a cent now.