Chemistry - December 2007

its from a chemistry lab. the labs bout mixtures that are soluable or insoluable. i dont get it...

2007-12-19 09:10:52 · 4 answers · asked by MusicFreak 3

Carbon disulfide is an important industrial solvent. It is prepared as follows 5C +2SO2 ----> CS2 + 4CO

a) How many moles of carbon disulfide form when 6.30 moles of carbon reacts?

b) How many moles of carbon monoxide are formed when 0.762 moles of carbon disulfude are produced? :(

2007-12-19 09:10:20 · 2 answers · asked by Anonymous

compressible, the shape
condensed, the shape
condensed, the volume and shape
compressible the volume and shape

2007-12-19 08:54:52 · 9 answers · asked by free g 1

My science fair experiment involved non-ferrous (not containing iron) metals and their reactions with concrete. The aluminum created a yellow gunky substance. Does anybody know what this is? Even if you aren't sure, could you just give me a list of aluminum compounds? I could figure out the answer from there.

2007-12-19 08:47:49 · 2 answers · asked by Tomboy with girly tendencies 4

2007-12-19 08:29:41 · 7 answers · asked by tony g 1

I am doing an assignment in chemistry on unknown organic chemicals.

Through various test like:- solubilty in H2O, Solubilty in NaHCO3, 2, 4 DNP and Lucas test - which has shown that the chemical is a secondary alcohol.

The mass spectrum which I was given had peaks at 31, 42, 55 (which I have found the answers too) - but I am unable to find what MW of 70 could be.

Can any off you good people help - you will acknowledgement in the bibliography. PLEASE!!!

2007-12-19 08:29:31 · 4 answers · asked by Cilla D 1

If I was going to buy a chemical where the size was described as 1 mCi; 37 MBq, what does this mean? How much is that in normal weight? Thanks.

2007-12-19 06:59:14 · 2 answers · asked by fruitytuttytutty 4

Find the solution set for y:

(3/4)y < 9 AND -(1/3)y <= -15

2007-12-19 06:00:20 · 1 answers · asked by Confused 1

What is the science on this one? Is it the removal of oxygen? the elemination of heat source??

2007-12-19 05:44:25 · 13 answers · asked by Snowtime 2

ok so in this chemistry problem

37.2 + 18 = 55.2

wouldnt the answer be just 55, since 18 has the least number of digits after the decimal point?

2007-12-19 04:22:16 · 8 answers · asked by sharizzle 1

A(g)+B(g)----> C(g) +D(g) ; if amount (in mol) of B(g) is doubled , % of B converted into products will be: Ans..33.33%

2007-12-19 03:23:24 · 1 answers · asked by Anonymous

2007-12-19 01:56:12 · 1 answers · asked by mason e 1

1. at 525 mm Hg and 85 degrees C, the volume of a sample of nitrogen gas is 26.8 L. What is the volume at STP?

a. 1 L
b. 10.9 L
c. 15.3 L

is it b?


2. when a 0.500 mole of sodium is produced according to the reaction 2NaN3 -->3N2 + 2Na, how many moles of nitrogen gas are also produced?

a. 0.750 moles
b. 1.5 moles
c. 2 moles
d. 3 moles

is it a?


3. a cylinder of compressed gas has a volume of 3.85 L and a pressure of 463 kPa. What volume would the gas occupy if it were allowed to escape into a balloon at a pressure of 110 kPa? Assume constant temperature.

a. 11.5 L
b. 16.2 L
c. 22.4 L
d. 28.9 L

is it c?


4. a cylinder contains 6.94 L of a gas at a temperature of 15 degrees C. The cylinder is heated, and a piston moves in the cylinder so that constant pressure is maintained. If the final volume of the gas in the cylinder is 8.50 L, what is the final temperature?

a. 12.2 degrees C
b. 38 degrees C
c. 54.6 deg C
d. 80 deg C

is it b?

2007-12-19 01:48:33 · 2 answers · asked by Anonymous

2007-12-19 01:48:19 · 5 answers · asked by Anonymous

Nitrogen in its normal state exists as a diatomic molecule.
Three significant figures are sufficient for your answer.

2007-12-19 00:31:08 · 2 answers · asked by Tiana 2

i want a short answer for this also do mention that y not stoppers of other materials like wood metal etc...

2007-12-18 22:45:45 · 2 answers · asked by midhat khatri 1

why it is happening like this?

2007-12-18 19:20:32 · 1 answers · asked by vinod.t.v 1

Which of the following compounds is a weak electrolyte?
a. HCL
b. CH3COOH(acetic acid)
c. C6H12O6(glucose)
d. O2
e. NaCl

2007-12-18 18:25:46 · 2 answers · asked by Anonymous

2007-12-18 17:41:29 · 2 answers · asked by Oh, it's like that? 7

a gas weighing 22.40 g occupies a 10.00-l flask a 27C and 722 torr of pressure. What is the molar mass of the gas?

2007-12-18 15:29:19 · 5 answers · asked by ngurl 2

Metallic cobalt crystallizes in a hexagonal close-packed structure.

2007-12-18 15:24:11 · 2 answers · asked by Jonathan 2

like what should i look out for that lets me know when to use the ideal gas laws instead of combined gas law.

2007-12-18 13:56:51 · 1 answers · asked by Anonymous

write a balanced chemical equation when sodium & oxygen combine to form sodium oxide [Na2O]

2007-12-18 13:55:26 · 2 answers · asked by Anonymous

Polars dissolve in polar and nonpolars in nonpolars. Can I get more details?

2007-12-18 13:50:39 · 2 answers · asked by sarah901167 2

If you have any links to them that can help too...Thank you in advance :-D

2007-12-18 13:38:07 · 1 answers · asked by loone 2

i'm having trouble with this problem:
you are given a white crystalline powder that melts at 450 degrees celsius. you are told that the compound may either be NH4(subscript 4)Br or NO2(subscript2). what is the identity of the compound?

another problem i'm having is figuring out what a central atom is cuz i forgot(oops :) ) can you tell me wat a central atom of C2H4

thankx bunches :)

2007-12-18 13:19:12 · 2 answers · asked by Chocolate_High 2

So I'm writing a story my character's running from the bad guys + ends up hiding behind the counter type thingy that's holding all the elements in liquid form (long story as to how it got to that) and I need to know is there any chemical combination you could put in an empty water bottle type thing + you could drop a match in it + has a slow enough reaction time to add the lid + toss it then it would burst into flames thus exploding the bottle + basically making like a fire bomb? I/f so what is it called + what's some other information on it. please + thank you for the help.

2007-12-18 13:05:19 · 3 answers · asked by Mary 1

find the percent composition of a compound containing tin ahd chlorine if 18.35g of the compound contains 5.74g of tin

help me understand how you did it

2007-12-18 12:55:27 · 3 answers · asked by theskyzblu 2

I got a chem final 2morrow And this is 1 of the concepts
How do You determine this?

For example
my study guide says
example:H2O.

Electronegativity O - Electronegativity H
3.44-2.20=1.24

The electronegativity between H and O is 1.24.

Therefore, H2O is polar covalent.

How do you know
O is 3.44 AND H is 2.20??

And another question.
Any good websites for polar & non polar bonds
like just a good site for explaining them well.

any Answer to these 2 questions.
THANKS

2007-12-18 12:50:41 · 7 answers · asked by Ace® 4

Im looking at equations, and I need to figure out what the precipitates that are formed in each of them..

One of which is:
Pb(NO3)2+Na2CO3 --> PbCO3+2NaNO3

Could I get some advise on how to find out what turns out to be the precipitate, and what is the (aq)?

2007-12-18 12:42:47 · 6 answers · asked by Anonymous