Chemistry - November 2007

SOMEONE PLZ HELP!!!!!

2007-11-05 12:45:29 · 5 answers · asked by thinkaboutit 2

to determine if a substance is pure, looking for this, in a standard reference tabl, will help you identifly the substance.
a. crystal structure
b. colour
c. state
d. density

2007-11-05 12:42:24 · 2 answers · asked by Joanne M 1

2007-11-05 12:40:35 · 9 answers · asked by Trisha P 1

2007-11-05 12:32:15 · 1 answers · asked by Anonymous

2007-11-05 12:31:22 · 1 answers · asked by Anonymous

2007-11-05 12:23:56 · 1 answers · asked by Anonymous

(b) What is the wavelength of radiation that has a frequency of 5.4 1012 s-1?

2007-11-05 11:48:19 · 3 answers · asked by Circuiteer 1

how is it? me and my mother can't agree.....
thank you

2007-11-05 11:44:39 · 13 answers · asked by ♥ my lady of sorrows ♥ 4

2007-11-05 11:43:45 · 1 answers · asked by Anonymous

I have two problems to solve that I don't know how to do,I missed school last week and the teacher gave me the worksheet,but I couldn't get a copy of the notes that explained how to do it,haha.
1)A block of aluminum occupies a volume of 15.0 L and weighs 40.5 g.What is the density?
2) Mercury metal is poured into a graduated cylinder that holds exactly 22.5 mL.The mercury used to fill the cylinder weighs 306.0 g.From this information,calculate the density of mercury.
I know that density=mass/volume,but I don't know the relationship between volume,mass,and weight.Anyone care to give me a hand?

2007-11-05 11:40:37 · 3 answers · asked by Lindsey 3

a gas or a liquid

2007-11-05 11:40:08 · 2 answers · asked by jorden r 1

Nickel has a face-centered cubic unit cell. The density of nickel is 6.84 grams per centimeter cubed. What is the atomic radius, in angstroms, of nickel?
Atomic weight of Nickel = 58.71 g/mol

2007-11-05 11:37:18 · 3 answers · asked by Anonymous

a) A simple cubic unit cell contains a total of four atoms

b) A body-centered cubic unit cell contains a total of two atoms

c) A face-centeed cubic unit cell contains a total of six atoms

d) In a cubic close-packed structure each sphere has twenty four nearest neighbors

2007-11-05 11:35:29 · 2 answers · asked by Anonymous

Calculate the molarity of a solution of NaOH if 34.22mL of this base reacts completely with 48.52mL of 0.1245M (molarity) HNO3 (aq)?

Please help, im stuck!

2007-11-05 11:27:03 · 1 answers · asked by thisiswhatsup 1

I realy need some help with this
Balance the following redox reaction:
a))KMnO4(aq)+HCl(aq)->MnCl2(s)+KCl(aq)+Cl2(g)+H2O(l)

Thanks

2007-11-05 11:22:35 · 1 answers · asked by elaisa 1

2007-11-05 11:14:54 · 2 answers · asked by jelly 1

2007-11-05 10:58:07 · 2 answers · asked by Mac 2

I do not get it. Please explain it in the most detail as possible cause Ive been on several websites and still dont understand. Examples would be really appreciated, they help me to understand! Thank You!

2007-11-05 10:47:18 · 1 answers · asked by Me 3

The purpose of this question is in regard to the possiblity of life forming on another planet where there is no water present.

2007-11-05 10:36:09 · 2 answers · asked by jeffdanielk 4

2007-11-05 10:35:00 · 4 answers · asked by DeeDee 1

im doing a project on the element chlorine and i cant seem to find these online, can anyone help?

Ion it likes to form:
Reactivity and compounds it forms:
Estimated amount of element on earth:

and if you have any interesting facts thatd be good too :)

2007-11-05 10:30:24 · 3 answers · asked by christine 3

I really want to know how to tell the bond length. I'm sure it's not like atomic radii, where you have two bonded atoms and see the distance from the two nuclei. In my book, it says that bond length is the average distance between two bonded atoms.

Also, Are double bonds stronger than single bonds?

Also, for resonance structures, for like SO2, why would there we more than one correct lewis structure. Can't you rotate the oxygens, so it's the same thing still?

If you could help, that would be awesome

2007-11-05 10:24:56 · 3 answers · asked by Anonymous

My roomate and I are debating wheather oxygen is released from water when boiled. I say that boiling would not break any oxygen from the H2O molecules. But, I realized maybe it would release the oxygen dissolved in the water, like what fish breath. What is the answer?

2007-11-05 10:20:14 · 5 answers · asked by Man of Action 3

Like n-propyl or n-butyl.

2007-11-05 10:13:16 · 2 answers · asked by Melissa 2

2007-11-05 10:12:31 · 3 answers · asked by Cherry 1

how do you find the mass of 100 cm of oxygen? how do you find the mass of 200cm of hydrogen?

2007-11-05 10:08:58 · 4 answers · asked by trccj 2

a sample of magniesium metal was allowed to react with excess hydrochloric acid solution. the gas liberated was collected over water at 23degrees celceius. The volume of gas collected was 47.1 mL and the atmospheric pressure in the lab was 744 mm Hg. the vapor pressure of the water at 23 degrees is 21.1 mm Hg.

a) write a ballanced equation for the reaction described above.

b) what volume in mL would the gas occupy if it was dryed and stored at STP

c)determinethe mass of magneisium metal in grams that would need to be reacted to liberate the quantity of the gas collected above

tell the equations used in your calculations.

2007-11-05 10:03:22 · 2 answers · asked by daniel T 3

explain with excellent proof...ty ^-^ and plz suggest how to draw the bohr diagram transferring electrons ty

2007-11-05 09:49:26 · 1 answers · asked by Anonymous

1)WHICH REACTANT IS LIMITING..SALICYLIC ACID OR ACETIC ANHYDRIDE?

2)WHAT IS THE THEORETICAL YIELD OF ASPIRIN?

3)IF I OBTAINED 1.789G OF ASPIRIN, WHAT IS THE PERCENT YIELD? REALLY CONFUSED

2007-11-05 09:21:10 · 1 answers · asked by frenchies 2

if your percentage yield varies from 100% explain what might have effected your yield?

If you percentage equals to 100% explain why this may or may not be a correct value?

THE ASPRIN I WEIGHTED IS 1 GRAM AND IT ASKED THE THEORETICAL YIELD OF ASPIRIN AND PERCENTAGE YIELD OF ASPIRIN

2007-11-05 09:16:54 · 1 answers · asked by frenchies 2