Chemistry - November 2007

if tanning booth lamps also emit ultraviolet radiation, but the client's skin remains cool. Does the lack of heat produced by these lamps make this type of tanning any safer than sunbathing? why or why not?

2007-11-12 09:01:57 · 1 answers · asked by Rosanna D 1

2007-11-12 08:56:03 · 1 answers · asked by GargVK 7

2007-11-12 08:48:25 · 1 answers · asked by Anthony G 1

2007-11-12 08:48:10 · 2 answers · asked by Anonymous

is there any hints to solve these gas laws? when to change atm to torrs and volume to liters?i guess im confused when to solve for T2 V1's is it like inverse operation or something?

2007-11-12 08:45:35 · 1 answers · asked by Marla S 1

The electron in the first hydrogen atom is in the n=1 level. The electron in the second hydrogen atom is in the n=4 level.

a.Which atom has the ground state electron configuration?

b.Which atom can emit electromagnetic radiation?

c. In which atom is the electron in a large orbital?

d.Which atom has a lower energy.

Thanks a lot if you help!

2007-11-12 08:44:49 · 1 answers · asked by Torrent4223 1

Predict whether each of the following oxides is ionic or molecular.
MgO

-ionic
-molecular
Na2O

-ionic
-molecular
XeO3

-ionic
-molecular
SO3

-ionic
-molecular
SrO

-ionic
-molecular
N2O

-ionic
-molecular
SO2

-ionic
-molecular

2007-11-12 08:41:28 · 2 answers · asked by Anonymous

2007-11-12 08:39:53 · 1 answers · asked by Anonymous

What would have been the final temperature of the watere?

2007-11-12 07:05:15 · 5 answers · asked by qwee 1

Calculate the wavelength of light emitted when each of the following transitions occur over the following in the hydrogen atom. What type of electromagnetic radiation is emitted in each transition?
a. n=3 →n=2
b. n=4→n=2
c. n=2→n=1

Calculate the maximum wavelength of light capable of removing an electronfor a hydrogen atom from the energy state characterized by n=1 and by n=2

2007-11-12 06:54:34 · 1 answers · asked by Anonymous

Given the same mass of each substance, why are the number of molecules present not the same?

2007-11-12 06:49:25 · 3 answers · asked by Jessi Z 3

Calculate the de Broglie wavelength for each of the following.
a. An electron with a velocity 10% of the speed of light
b. A tennis ball (55g) served at 35m/s (-80 mi/h)

A particle has a velocity that is 90% of the speed of light. If the wavelength of the particle is 1.5x10 to the power of -15m, calculate the mass of the particle

2007-11-12 06:41:21 · 1 answers · asked by Anonymous

Elemental ananalysis of a compound results in the following data
65.45 % C
5.49 % H
29.06 % O

4.13 g of the compound fills a 184.0 ml bottle with a pressure of 2501.7 mm Hg at a temperature of 22.1oC. What is the molecular formula of this compound ?

2007-11-12 06:34:39 · 3 answers · asked by Anonymous

science thing...

2007-11-12 06:33:26 · 1 answers · asked by n986621 2

2007-11-12 06:11:58 · 6 answers · asked by V W 1

Arrange the following atoms in order of increasing effective nuclear charge experienced by the electrons in the n = 3 electron shell.
K, Mg, Ti, Rh, P

2007-11-12 04:37:50 · 1 answers · asked by Anonymous

Enter a numeric answer only, no units.

2007-11-12 04:30:13 · 1 answers · asked by Anonymous

2007-11-12 03:18:45 · 1 answers · asked by globalcrook 1

Calculate the mass in grams of solid sodium hypochlorite that would need to be added to a swimming pool of volume 1.5 x 10^4 gallons to achieve a chlorine (not hypchlorite ion) concentration of 3ppm. Note: 1 gallon is 3.79 liters and the density of the pool water is 1.0g/mL.

2007-11-12 02:36:21 · 1 answers · asked by RussianSoccer3 1

I had a question about how to create mapping equations for physical chemistry. He mentioned it once in class, but it's nowhere in the book at all, and we need to use it alot.
Anyways, could someone please explain how to derive a mapping equation for example, finding the mapping equation for chemical potential at fixed T then fixed p.

Thanks!

2007-11-12 01:31:13 · 1 answers · asked by Skeez 3

It says in the periodic table that Chlorine has a relative atomic mass of 35.5.

2007-11-12 00:35:52 · 4 answers · asked by Anonymous

Help us to resolve the argument please

2007-11-11 23:36:01 · 6 answers · asked by anna d 2

Which one of the following is a positive ion?
(a)Beryllium
(b)Boron
(c)Carbon
(d)Nitrogen
(e)Neon

2007-11-11 19:08:56 · 3 answers · asked by jess_me 2

Please help me!!!!

2007-11-11 18:10:03 · 2 answers · asked by Anonymous

Starting with 13.2 ml of 4.10 x 10-2 M BaCl2, how many grams of ZnSO4 can be added to the solution before BaSO4 begins to precipitate ?

2007-11-11 16:46:09 · 1 answers · asked by Anonymous

Assume reaction driven by bacterial culture in an aqueous solution.

2007-11-11 16:10:14 · 1 answers · asked by B H 1

I hate chemistry homework!

2007-11-11 16:07:14 · 5 answers · asked by ? 2

need answer as soon as possible

2007-11-11 16:00:25 · 4 answers · asked by thekeeper7 2

to its pressure on the container?

2007-11-11 15:51:16 · 6 answers · asked by Anonymous

A) Sn2+
B)Au+
C)Zn2+
D)N3-
E)Se2-
F)Br-
G)Ba2+
H)In3+
I) F-

2007-11-11 15:38:20 · 1 answers · asked by Anonymous