Chemistry - March 2007

One is bioluminence I think....

2007-03-28 13:19:24 · 4 answers · asked by Claire 4

A 0.226 g sample of CO2 has a volume of 525 ml and a pressure of 455 mm Hg. What is the temperature of the gas?

note here--PV=nRT
R=0.0821 L atm/mole K

2007-03-28 13:18:29 · 6 answers · asked by Anonymous

ASAP HELP!

2007-03-28 13:11:54 · 2 answers · asked by krntigerchick_punk 2

Solve for the new temperature in degrees C when the following pressure changes occur, with constant n and V:

a) A 10.0-L container of helium gas with a pressure of 250 torr at 0 degrees C is heated to give a pressure of 1500 torr.

b) A sample of air at 40 degrees C and 740 mm Hg is cooled to give a pressure of 680 mm Hg.



Please explain the work, Thanks!

2007-03-28 12:59:16 · 2 answers · asked by StarletGirl 1

A gas has a volume of 4.00 L at 0 degrees Celcius. What final temp. in degrees C is needed to cause the volume of the gas to change to the following, if n and P are not changed?

a) 10 L
b) 1200 ml
c) 2.50 L
d)50.0 ml


Note: V1/T1=V2/T2

2007-03-28 12:54:26 · 1 answers · asked by StarletGirl 1

And.. how is the behavior of isotope different? PLZ HELP! ASAP!

2007-03-28 12:43:35 · 5 answers · asked by krntigerchick_punk 2

2007-03-28 12:29:53 · 3 answers · asked by hyperfluffball 1

2007-03-28 12:14:37 · 1 answers · asked by Sarah W 1

Science help!!! please?
Science help!!! please?
1.The density of water = 1.0 g/ml, gycerol = 1.26 g/ml , and oil = 0.9 g/ml. These density are similar. However, their ranking for flow rate is different. Why their flow rate is different?

You can explain it like this-
Explain using the particle theory. Particle theory states all matter is made up with tiny particles.

answer the question no 1 or answer it by using the particle theory.
Please help me.

2007-03-28 12:11:48 · 3 answers · asked by dkhgvusdygv 1

What is the limiting reactant

given AgNO3 + NaCl= AgCl+ NaNO3

2007-03-28 12:07:11 · 2 answers · asked by molly 1

2I − + Br2 = I2 + 2Br−

Calculate the standard free energy change in kJ/mol for the above cell reaction

2007-03-28 12:05:37 · 1 answers · asked by Bryant M. 4

2007-03-28 11:58:35 · 6 answers · asked by hyperfluffball 1

??? what affects radioactive decay.

2007-03-28 11:44:21 · 2 answers · asked by krntigerchick_punk 2

Hi everybody, I'm doing a science experiment where I'm pouring 100% pure ethanol into a bottle, placing that plastic bottle into a pot,and placing the pot onto a stove, and raising the temperature to 30-40 degrees C. I'm not sure if this is safe, b/c the bottle says that pure ethanol should not even be exposed to sunlight for long amounts of time.
please consider your response carefully because this is a potentially dangerous experiment, and I am taking all responses seriously.

2007-03-28 11:39:32 · 3 answers · asked by J Z 4

If the radioactive isotope is half- life of 100 years is 40 g isotope than how much mass in 200 yrs?

2007-03-28 11:38:16 · 2 answers · asked by krntigerchick_punk 2

How long does it take for 65.0% of a sample of 32P to decay?

2007-03-28 11:23:00 · 1 answers · asked by crazzyangel16 1

2007-03-28 11:19:45 · 1 answers · asked by bdgurl5388 1

An electrolytic cell is used to plate silver from a silver nitrate solution onto an electrode. How much time (in seconds) is required to deposit 8.0 g of silver if the current is kept constant at 5.0 amperes? Assume 100% current efficiency. (F = 96480 C/mol e-)



a. 2.5 x 10^4 s

b. 2.6 x 10^5 s

c. 5.9 x 10^4 s

d. 1.4 x 10^3 s

e. 170 s

2007-03-28 11:19:33 · 1 answers · asked by Anonymous

2007-03-28 11:11:53 · 1 answers · asked by mandm 2

so can some1 plz balance: __H2 + ___CO2 ---> ___CH3OH

2007-03-28 11:04:38 · 3 answers · asked by cooldude123 2

Calculate the pHof a solution prepared by mixing 20.5 mL of a .5M sodium fluoride solution with 32.5 mL of a .75 M hydrofluoric acid solution.

No Ka is given. Would I work this with an SRF table or what?
Using an SRF table, I got pH=3.34.

2007-03-28 11:04:37 · 1 answers · asked by Es Macht Nichts 2

2HCI + Ca(OH)2 ------------ 2H2O + CaCI2
(not sure if I have the correct balance equation.)

2007-03-28 10:41:28 · 1 answers · asked by shortydidi03 2

2007-03-28 10:30:33 · 4 answers · asked by Anonymous

2007-03-28 10:24:52 · 1 answers · asked by Sparkles 2

how many ions dissociate in Al(cl)3
or do any?

2007-03-28 10:24:26 · 5 answers · asked by mitchel l 2

ok...5.87g of Mg(OH)2 reacts with 12.84g of HCl to form MgCl2 and water. I have the balanced equation but im not sure what to do after that..Please help THANKS!!

2007-03-28 10:23:36 · 4 answers · asked by Kelsey S 1

2007-03-28 10:23:02 · 4 answers · asked by Anonymous

I really need the help, I tried and handed it up to my teacher but she let me re-do it because she said I left out reference to conc. of H2SO4 and info on it being a condensation reaction. The apparatus used was ethanol and butan-1-ol, glacial ethanoic acid, conc. H2SO4, measuring cylinder,boiling tube and beakers. You can include any helpful tidbits as well because I can use all the help I can get. And, if anyone knows how, describe using equations and conditions, what happens when an ester(ethyl ethanoate) is heated with aqueous sodium hydroxide. Thanks for the help!(in advance)

2007-03-28 10:22:39 · 4 answers · asked by deadly_plague101 1

1-bromo-3-methylcyclopentane

m-chlorotoluene

2007-03-28 10:16:10 · 1 answers · asked by shortydidi03 2

2007-03-28 10:15:31 · 2 answers · asked by Me 3