Chemistry - March 2007

why does firework explode when you shake it?

2007-03-05 20:58:52 · 1 answers · asked by Anonymous

1.Monohydrate Dextrose 2.glucos syrup 3.citric acid mono 4. vitamin e oil 5.vitamin e 50% powder feed grade 6.monohydrate sodium glutamate 7.corn starch food grade 8.nisin

2007-03-05 20:24:05 · 3 answers · asked by Anonymous

How many buffer regions exist for a polyprotic acid?

a. One. There is only one buffer region no matter how many titratable protons there are in the acid.
b. one less than the number of acidic hydrogen ions
c. one more than the number of acidic hydrogen ions
d. one, but it is really, really large.
e. there is one buffer region for each of the titratable protons in the acid. It may be difficult to discern all of them from an experimental potentiometric titration curve, but they all exist.

2007-03-05 20:18:26 · 1 answers · asked by Justin_d12 1

2007-03-05 20:18:17 · 2 answers · asked by Lai Yu Zeng 4

2007-03-05 20:15:06 · 1 answers · asked by Lai Yu Zeng 4

I want to work out the standard entropy change of combustion for alcohols. I have the mass of the alcohol at the start and at the end of the experiment but I am now stuck. How do I work it out!

2007-03-05 20:08:11 · 2 answers · asked by aliwhitby2000 1

E.g. a visking tubing containing water is put into a beaker containing water as well...the volume of water is the more as compared to in the visking tubing...why the molecules of water are always equal in amount??

2007-03-05 20:07:45 · 2 answers · asked by wei jun 1

If a few drops of the indicator phenolphthalein had been intitially added to the analyte prior to the titration, how many times would you observe a color transition from colorless to pink?
a. never
b. once
c. twice
d. three times
e. four times

2007-03-05 20:06:46 · 2 answers · asked by Justin_d12 1

2007-03-05 19:14:26 · 2 answers · asked by sara 1

write an equation to illustrate the formation of methyl salicylate from salicylic acid and methyl alcohol.

pls and thanks

2007-03-05 18:24:11 · 2 answers · asked by Anonymous

2007-03-05 17:41:28 · 8 answers · asked by deidre m 1

Calculate the velocity of an elecrton that produces an ultraviolet light at a wavelength of 250 nm

2007-03-05 17:39:15 · 2 answers · asked by shane200388 1

Calculate the longest and shortest wavelength associated with the electron transition to the seventh energy level (m=7) withing a hydrogen atom.

2007-03-05 17:38:02 · 2 answers · asked by shane200388 1

The laser light used in CD players has a wavelength of 780 nm. Calculate the energy and frequency of the wavelength of light.

2007-03-05 17:36:24 · 3 answers · asked by shane200388 1

Balance the following net ionic equation by using either the oxidation number or the half reaction method in an acidic solution?

BrO3 + Fe(2+ charge) --> Br(-) +Fe(3+ charge)

2007-03-05 17:34:59 · 1 answers · asked by shane200388 1

I know this question isn't phrased right. But I am trying to find out: when water freezes into ice, it compacts. What is the difference in volume? In other words, water is packed into an ice cube, and it's volume is bigger when melted. What is the ratio, if there is one?

2007-03-05 16:59:53 · 3 answers · asked by classical_maniac101 3

For instance, can 2SO3 be the reactant in the dissociation reaction

2SO3 = 2 SO2 + O2?

2007-03-05 16:40:48 · 2 answers · asked by Anonymous

In H2O2, the Oxygen has an ion of 1-, why???

Please help.

2007-03-05 16:21:48 · 0 answers · asked by blackmail8549 2

If you begin a reaction with 7.7g of I2(iodine) vapor and 6.3g of Br2(bromine) vapor in a 1.00L container, what is the concentration of IBr at equilibrium. Kp = 120
I2 (g) + Br2 (g) <-> 2IBr (g)

_-- please try and show step by step. Thanks

2007-03-05 16:12:38 · 1 answers · asked by Anonymous

help

2007-03-05 16:08:37 · 4 answers · asked by esrarengizbeauty 1

2007-03-05 16:06:10 · 7 answers · asked by SidBridge 6

2007-03-05 15:54:40 · 1 answers · asked by Anonymous

I got 8.9, is that right?

2007-03-05 15:48:04 · 1 answers · asked by Anonymous

pH of a 0.22 M solution acrylic acid = 2.46. % dissociation of a 0.22 M solution of acrylic acid = 1.6%. The pH of a 0.037 M solution of sodium acrylate = 8.41.

2007-03-05 15:43:25 · 1 answers · asked by 2badcats 2

Please write a chemical equation in this case of:

1. "Magnesium Oxide is heated"

2. "Sodium Metal reacts with water"
(Sodium does go to flame upon water contact, doesn't it?)

Many thanks.

2007-03-05 15:22:27 · 1 answers · asked by Spectator 3

equation used Pi=MRT

The osmotic pressure of blood is 7.65 atm @ 37 degrees C. What mass of glucose is needed to prepare 2.50 liters of solution for intravenouse injection? The osmotic pressure of the glucose solution must equal the osmotic pressure of blood. R=0.08206 L*atm/mol*K

7.65 atm=(m) 0.08206 L*atm/mol K *310 degrees K

= 7.65 atm/25.44 L*atm/mol*301 L/mol

2007-03-05 15:13:31 · 1 answers · asked by ~~Shelly~~ 2

what is the concentration of the NaOh solution?

2007-03-05 15:08:10 · 1 answers · asked by universitystudent 2

What is the freezing point of solution containing 6.78 grams Naphthalene (molar mass is 128.2 g/mol) dissolved in 16.0 grams paradichlorobenzene? the freezing point of pure paradichlorobenzene is 53.0 degrees C/ The freezing point depression constant is 7.10 degrees C/molal ( I think that the 7.10 would be Kf??? right)
Please explain how to figure this. ..?? Thanks!

2007-03-05 15:01:13 · 1 answers · asked by ~~Shelly~~ 2

The equation I have doesn't seem to fit???
? Delta Tbp=Kbp(m)??? is this the equation I would use?

what is the boiling point of a solution containing 4.66 g of caffeine
C8 H10 N4 O2 dissolved in 15.0 g of benzene?
The boiling point of pure benzene is 80.1 degrees C. The boiling point elevation constant Kb = 2.53 degrees C/molal

2007-03-05 14:52:03 · 3 answers · asked by ~~Shelly~~ 2

"likes dissolve likes"
someone explain. why. i know what polar molecules are so don;t bother explaing that. but why would a non polar dissolve in a nonpolar solution?

2007-03-05 14:47:19 · 1 answers · asked by applejacks 3