Science & Mathematics - 27 September 2007

So ive been working on this problem and i dont know if i got it right so please help me!! and show me the work so if i did get the wrong answer i can see where i went wrong.

The percentages by mass of C, H, N, and O, in an unknown compound are found to be 23.3%, 4.85%, 40.78% and the rest is oxygen respectively.

A) determine the emperical formula for this compound


B) If the molar mass of the compound is 206g mol(-)1 what is the molecular formula?

thanks a million!

2007-09-27 12:02:22 · 4 answers · asked by Riley 1 in Chemistry

True or false (yes or no, 1 or 0) problems with wrong-answer penalties:
a) 75-ohm cable are used for analog transmission
b) Single-mode fiber are more expensive but are widely used for longer
distances than multi-mode fiber
c) Downlink are always have higher frequency than uplink for satellite
communication
d) We need at least 4 geostationary satellites to cove the whole earth
surface

2007-09-27 12:01:54 · 1 answers · asked by student 1 in Physics

Also describe any ways in which the analogy is not perfect?

2007-09-27 12:00:30 · 7 answers · asked by Linda H 1 in Biology

2007-09-27 11:57:58 · 4 answers · asked by Dalila 1 in Mathematics

2007-09-27 11:53:24 · 6 answers · asked by LOLO 3 in Weather

I live in western Washington state. This time of year, a bug comes out that my kids and I simply call "Fairy bugs."
It's a tiny flying insect that looks a bit like a gnat (could be kind of gnat) but flits lazily through the air. It doesn't bite or attempt to go anywhere in particular.
What makes it look like a fairy is it has fine blue hairs on its body. Looking close, it actually looks as if the blue hairs are down-like feathers.
They are pretty little bugs. I would like to know if anyone knows what they are called or a source where I could look it up.

2007-09-27 11:50:55 · 1 answers · asked by thezaylady 7 in Zoology

y=4-x Where did I screw up?

2007-09-27 11:49:07 · 4 answers · asked by Dalila 1 in Mathematics

what does it have to do with beavers?

2007-09-27 11:48:43 · 3 answers · asked by historyman 1 in Biology

Nutrients that contain nitrogen,as well as carbon,hyrdrogen, and oxygen are called ________.

2007-09-27 11:48:36 · 1 answers · asked by mom 1 in Other - Science

2007-09-27 11:47:49 · 1 answers · asked by jovy_rjl 1 in Physics

2007-09-27 11:47:08 · 5 answers · asked by yortfoaneleh1 1 in Astronomy & Space

2007-09-27 11:46:43 · 7 answers · asked by mirokuzlover 1 in Astronomy & Space

when you see something moving in the microscope like to the top and the the right, do you really see the opposite of that through the eyepiece? and second, why do we have to focus the low-power objective first?

2007-09-27 11:44:43 · 2 answers · asked by Justin P 1 in Other - Science

An electric heater draws a current of 5.9A when it is plugged into a 120 V household power supply. How much does it cost if this heater is operated for 3.5 hours with 120 V household power supply? ( electrical energy costs 13 cents per KWh

Please show work

2007-09-27 11:42:20 · 2 answers · asked by mastersource2005 5 in Physics

I live in Oklahoma and I found this bug at the park and I have no idea what it is.

http://i136.photobucket.com/albums/q198/coloring_land_hero/bug1.jpg

2007-09-27 11:41:49 · 1 answers · asked by Stephanie B 2 in Zoology

2007-09-27 11:41:43 · 4 answers · asked by Kev 2 in Biology

My dughter's homework is very difficult. Can you please help? It goes like this: "At Irv's Cycle Rental Shop, Irv rents all kinds of cycles: unicycles, tandem bikes, regular bikes, and even tricycles for little kids. He parks all the cycles in front of his shop with a helmet for each rider strapped to the cycles. This morning Irv counted 57 helmets and 115 wheels parked in front of his store. He knows he has an equal number of unicycles and tandem bikes. He also knows that he has 32 regular bikes. How many unicycles, tandem bikes, and tricylcles does Irv have?" Please help her. Tell me how you got the answer. And not just an answer. If you don't know the answer but know how to work it. Please tell me that too. Thanks.

2007-09-27 11:41:20 · 2 answers · asked by tagamargos 1 in Mathematics

2007-09-27 11:41:11 · 11 answers · asked by lisa s 2 in Other - Science

HELP!! I really need the answer!

2007-09-27 11:40:41 · 2 answers · asked by Isabella 2 in Other - Science

Do you agree or disagreebthat homologous chromosomes are found in gametes. Why do you agree or disagree.

yea i really don't understand this question.
can anyone help me?

2007-09-27 11:37:34 · 5 answers · asked by Lizzy 2 in Biology

Would it gain or lose mass because of osmosis?

2007-09-27 11:35:51 · 1 answers · asked by Your Mom 3 in Biology

i asked once before, and didnt get a very good answer, so hopefully this time i get one that actually helps.

2007-09-27 11:35:27 · 2 answers · asked by Anonymous in Earth Sciences & Geology

Does the element helium ever form any chemical compounds?

All noble gasses are very stable because of a full outer shell of electrons. But xenon sometimes forms some compounds.
Are there any known compounds of He?

2007-09-27 11:35:14 · 2 answers · asked by Jeffrey K 7 in Chemistry

2007-09-27 11:35:04 · 9 answers · asked by Anonymous in Mathematics

2007-09-27 11:34:15 · 3 answers · asked by Melissa 1 in Biology

just a fun exercise in math

2007-09-27 11:27:12 · 8 answers · asked by Not Quite Agnostic 2 in Mathematics

2007-09-27 11:26:57 · 2 answers · asked by Taylor W 1 in Biology

explain the way you got the answer

2007-09-27 11:23:07 · 14 answers · asked by ~TATOR~ 1 in Mathematics

which one of those four is this?

f(x) = -2

2007-09-27 11:22:58 · 4 answers · asked by Anonymous in Mathematics

I have recently gotten into foraging wild edible plants and I am having trouble identifying which is wild lettuce and which is dandelion. They both look the same, making it hard to decipher which one is which. Any distinct differences that you know of that will help me out?

2007-09-27 11:22:43 · 4 answers · asked by KingOfTheDrews 2 in Botany