Chemistry - September 2007

The title explains all, if anyone knows please answer. thank you!

2007-09-22 15:01:42 · 8 answers · asked by Anonymous

Bornite (Cu3FeS3) is a copper ore used in the production of copper. When heated, the following reaction occurs.

2 Cu3FeS3(s) + 7 O2(g) 6 Cu(s) + 2 FeO(s) + 6 SO2(g)
If 4.48 metric tons of bornite is reacted with excess O2 and the process has an 83.7% yield of copper, what mass of copper is produced?

2007-09-22 14:54:47 · 2 answers · asked by s.weiss 1

why is it 3d10, NOT 4d10?

2007-09-22 14:53:01 · 3 answers · asked by nothingspecial 1

a. H2O molecules
b. CaCl2 molecules
c. Ca^2+ ions
d. Cl- ions

2007-09-22 13:18:44 · 3 answers · asked by Anonymous

a. it has the same concentration as Cl- ion
b. its concentration is half that of Cl- ion
c. its concentration is twice that of the Cl- ion
d. itsconcentration is one-third of the Cl- ion

2007-09-22 13:12:53 · 1 answers · asked by Anonymous

Please show a source! (Credible, of course)

2007-09-22 12:45:52 · 2 answers · asked by Anonymous

(There are also small pieces of aluminum inside the can.)

2007-09-22 12:44:03 · 2 answers · asked by jkgregory10@sbcglobal.net 1

Its CuSO4 + Na2CO3 produces CuCO3 + Na2SO4 and I need to find the percent yield, and CuCO3 is the precipitate. My theoretical yield is 0.615 g but for the actual yield I got 0.116 g so I was wondering what other people may have gotten for their actual mass.

2007-09-22 12:41:38 · 1 answers · asked by <3DA<3 1

How many moles of Cl2 would you need to add to have stoichiometrically equivalent amount of Na and Cl2?

2Na+Cl2 ---> 2NaCl

2007-09-22 12:40:34 · 2 answers · asked by Molly❀ 3

A 0.8000 g sample of impure sodium choride is dissolved in water, and the chloride is precipitated with excess silver nitrate, producing 1.000 g of silver chloride. What is the mass percent of sodium chloride in the original impure sample?

a. ) 40.77
b. ) 24.74
c. ) 50.97
d. ) 80.00
e. ) 0.6977

I worked it out and I got e). Is that correct?

2007-09-22 12:29:39 · 2 answers · asked by secondaryhoper 1

i dont know how to do ions

Mg2+
K+
Cl-

and try to explain to me how you got the answers
O2-

2007-09-22 12:24:47 · 2 answers · asked by Anonymous

2007-09-22 11:52:09 · 1 answers · asked by John D 2

2007-09-22 11:36:55 · 5 answers · asked by John 1

An unknown compound contains C, H and N. When 0.574 g was burned in a combustion apparatus 0.4187 g of H 2O and 1.1364 g CO 2 were produced. What is the empirical formula of the compound?
just tell me the procedure

2007-09-22 11:30:30 · 2 answers · asked by Anonymous

If a sample of the compound C 3H 2Cl 6 contains 21 moles of C atoms identify how many moles of Cl atoms it contains.

help plz.

2007-09-22 11:20:34 · 2 answers · asked by Anonymous

Ok, first off, this is for biology class...not chemistry...which is kind of weird to begin with (I thought it fit better in the chem category). I have to create a 3-D Bohr model of the atom carbon. One of the requirements is that protons, neutrons, and electrons are proportional. I thought that electrons were just a cloud/shells anyway, but I guess not according to this teacher...should I make the protons, neutrons, and electrons the same size, or different sizes? I have only seen them the same size...but I am only in high school...btw, this teacher is really...*cough* annoying, unreliable, confusing, dyslexic (no offense...) *cough* so I have trouble with her instructions sometimes...if they are the same size, please just say so. If not, say what sizes they should be, please! Thanks. (Sorry about the lengthy details.)

2007-09-22 11:19:27 · 6 answers · asked by mlygsby 3

please help, i am so lost on this lab I am doing.

2007-09-22 11:13:37 · 2 answers · asked by chemistryishard 2

The molecular formula for the compound CH 3COOH indicates there is a 1:3 molar ratio between the compound and the hydrogen atoms in that compound.

is it true or false?

help plz?

2007-09-22 10:57:39 · 4 answers · asked by Anonymous

Q: C6H5-NH2 + C6H5-OH <-----> C6H5-NH3(+) + C6H5-O(-)

pka of C6H5-OH = 10
pka of C6H5-NH3(+) = 4.6

A: I have determined that the answer is No (a reaction will not take place).. However, I have no clue why...Can someone explain it to me. Thanks!

2007-09-22 10:47:44 · 1 answers · asked by Jimmy 3

How do you wirte electonic configuration, how? method please for example NA, is 1s2 2s2 2p6 3s1 , (another think i dont get is 2s2)

2007-09-22 10:38:31 · 3 answers · asked by nothingspecial 1

a.) melted
b.) sublimed
c.) evaporated
d.) vaporized

2007-09-22 10:27:03 · 6 answers · asked by Anonymous

Can u please help me with this question because it seems that i can't find the answer.
What type of macromolecules do they belong to:
-NaCI
-estrogen/testosterone
-glucose
-cholestrol
-collagen
-glycogen
-steriod
-polysaccharide
-salt
-protein
-monosaccharide
Thanks for the help!!

2007-09-22 10:23:38 · 1 answers · asked by IvK*JH 2

At A-level how do you write electronic configuration?

2007-09-22 10:17:03 · 2 answers · asked by nothingspecial 1

I have CH3C=OSH and H2C=S=O=CH2...I wish I could draw the structures on here, but I'll leave that up to you upon checking. thanks!

2007-09-22 10:05:47 · 1 answers · asked by Jimmy 3

An unknown compound contains only carbon, hydrogen, and oxygen (CxHyOz). Combustion of 7.00 g of this compound produced 10.3 g of carbon dioxide and 4.20 g of water.

How many moles of carbon, C, were in the orginal sample?

2007-09-22 09:49:37 · 1 answers · asked by Cynthia P 1

apart from having the compound? just curious :) .... (don't need to go into detail)

2007-09-22 09:46:12 · 1 answers · asked by sathi 2

2007-09-22 09:38:09 · 4 answers · asked by Updated Life th13f 2

i know the atomic number is the number of protons, but how do you find out how many neutrons and electrons in it?

2007-09-22 09:31:27 · 2 answers · asked by kpajamas613 3

The Brown paper one, and the one where Sudan IV reagent is added...but what is the advantage? Thanks alot guys.
There is a similar question in the archives but wanted to see what others have to say. Thanks a bunch.

2007-09-22 09:22:39 · 1 answers · asked by Anonymous

this is an ion concentration problem
M stands for molarity

2007-09-22 09:18:15 · 1 answers · asked by Anonymous