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Chemistry - October 2007

[Selected]: All categories Science & Mathematics Chemistry

answer doesnt have to be right
i thought hydrogen..
but i need other examples to test.

2007-10-22 14:47:16 · 1 answers · asked by cityancolour 2

Why can't ammonia NH3 donate a proton (when in water) but ammonium NH4 can? and why can't ammonium accept a proton and ammonia can?

btw all I learned so far are 2 theories of acids/bases: Arrhenius and Bronsted-Lowry.

2007-10-22 14:40:34 · 4 answers · asked by Anonymous

Our class had to do an experiment on osmosis. We placed a potato cube into a salt mix water concentration for about 21 hours
and the cube gained weight. Our previous observations was that the cube lost weight. Can anyone explain why the potato cube would gain weight? Thx so much.

2007-10-22 14:40:02 · 2 answers · asked by Anonymous

& ORTHO & PARA DIRECTING GROUPS,META DIRECTING GROUPS

2007-10-22 14:31:24 · 2 answers · asked by Anonymous

I took my chemistry class in order to challenge myself mentally..and now I'm struggling. My question has to do with 4 questions on my study sheet that I really don't know how to do, and I'm going to need it is my guide for the next test. I would really appreciate it if someone could help me out with this if they get it. I don't know the answers, and although I have a kinda-sorta idea of how to get them, I don't have any answers to check it with. Care to try, anyone?

How many moles contain each of the following?
1.) 3.75 x 10^24 molecules CO2
2.) 3.58 x 10^23 formula unites ZNCl2

Determine the number of moles present:
a.) 22.6g AgNO3
b.) 6.50g HCL

thank you!

2007-10-22 14:23:30 · 3 answers · asked by .Vee. 1

Acidified solution of potassium permanganate is added to a solution of sodium sulfate.

2007-10-22 14:19:25 · 1 answers · asked by aaadaj 1

How many carbon-14 atoms from a sample of 800 C-14 atoms will remain after 2.0 half lifes?

2007-10-22 14:18:38 · 1 answers · asked by hello1 2

Hydrogen peroxide solution is added to an acidified solution of potassium dichromate,

what is the reaction

2007-10-22 14:18:37 · 2 answers · asked by aaadaj 1

K2O + H20 --> ?

2007-10-22 14:17:41 · 1 answers · asked by aaadaj 1

a little bit ago, the cap on a low power flame torch thing busted open and started spaying some kind of gas everywhere. basically it got really cold and started dripping some kind of liquid that froze what ever it touched, and nothing really happened besides that. should it be worried at all?

2007-10-22 14:09:58 · 7 answers · asked by et_phone_my_home 1

2007-10-22 14:09:54 · 21 answers · asked by Andrew F 2

In chem, we made stuffed moles and had to name em. I named mine Armoledilo (it's gray with black stripes), and now we have to write stories about our moles. Any ideas?

2007-10-22 14:04:48 · 2 answers · asked by Anita 5

i dont have a high tech calculater that will do this problem...will someone help me out?
(a) 1.7x10^-12
(b) 2.22
(c) 3.60
(d) 5.12
(e) 11.78

2007-10-22 13:59:10 · 1 answers · asked by Edgardo M 1

1.Label your beakers “beaker #1” and “beaker #2”
2.Use beaker #1 to find out the rate of reaction of peroxide with hydrogen peroxide and use beaker #2 to find out the rate of reaction of peroxidase with hydrogen peroxide.
3.Let the celery represent the peroxidase. Use a mortar and a pestle to mash the celery until liquid starts coming out. Keep on mashing until you have 4.2ml of the liquid. Use a graduated cylinder to measure.
4.After you have the correct amount of “celery juice” pour it into beaker #1. Also add 10ml of hydrogen peroxide into the same beaker. Set the beaker aside.
5.Next, add only a pinch of manganese dioxide with hydrogen peroxide in beaker #2 to find out the rate of reaction for it. Then measure out 4.2ml of “celery juice” and pour it into the beaker. (You will have to mash the celery again.)
6.Now that you have beaker #1 and beaker #2, measure the change of mass at an interval. Measure the beakers separately using 2 scales, one for each beaker. Start at 3

2007-10-22 13:51:18 · 2 answers · asked by Anonymous

2007-10-22 13:42:50 · 1 answers · asked by Paul K 2

Which would show the greatest and lowest ionization energy?
first ionization energy of boron,
first ionization energy of cesium,
second ionization energy of indium.
second ionization energy of strontium,
second ionization energy of xenon,
third ionization energy for calcium

2007-10-22 13:37:51 · 1 answers · asked by Anonymous

A. Chlorine B.Hydrogen C.Sulfur D.Magnesium.

2007-10-22 13:20:15 · 3 answers · asked by Mr.Nightfire 2

What is the temperature of 210K in celsius degrees?

2007-10-22 12:00:46 · 4 answers · asked by Anonymous

I did this and the pH that I got was 1.57 (I even checked for significant digits) but apparantly that is not the right answer.

2007-10-22 11:50:11 · 1 answers · asked by alfonsocarnucci 2

A 1.509 g sample of asmium oxide which melts at 40 C and boils at 130 C degrees is placed inot a cylinder with a movable piston that can expand against the atomospheric pressure of 745 torr. Whe the sample is heated to 200 degrees c, it is completely vaporized and the volume of the cylinder expandes by 235 mL. What is the molar mass of the oxide? Asuming that the oxide is OsOx, find X?

So what do I do? Pl. tell me how to do it. I have to study for the test tomorrow and I need help quickkkkkkkk.

~~thax~~*_*~~~

2007-10-22 11:24:24 · 1 answers · asked by Anonymous

Na2CO3 (aq)+HCl(aq) --> ???

I got all the other ones I need, but this one is stumping me...
=[ thanks for your help!

2007-10-22 09:58:11 · 2 answers · asked by bafisch89 1

2007-10-22 09:54:47 · 8 answers · asked by lx 1

is it metal or non metal? i'm thinking metal.

2007-10-22 09:49:30 · 3 answers · asked by Anonymous

its mole day tommorow and i neeed to know!

2007-10-22 09:21:14 · 11 answers · asked by cantwaittogetout 1

How many orbitals are contained in the third principal level (n=3) of a given atom?

2007-10-22 08:47:34 · 3 answers · asked by Jay H 1

These are true or false questions... Does fuels contain kinetic energy?

2007-10-22 08:45:45 · 9 answers · asked by Britt 1

Predict the chemical formulas of the compound formed by the following pairs of ions:

1) Cu+ and S 2- = Cu2S
2) Fe 3+ and O 2- = Fe2O3
3) Hg2 2+ and CO3 2- = Hg2CO3
4) Ca 2+ and AsO4 3- = Ca2O4 + As3
5) NH4 + and CO3 2- = (NH4)2CO3

2007-10-22 08:26:50 · 5 answers · asked by Whitney D 1

I have an idea for it already, making a scavanger hunt with normal household items using chemical symbols (ex. "Find something that contains NaCl) but I don't know how to go about doing that.

I can't find anywhere on the internet anything about it, like different compounds or elements that the products contain, any help here?

2007-10-22 08:13:00 · 3 answers · asked by Anonymous

If you dont know the relative densities????

2007-10-22 08:03:23 · 3 answers · asked by senthiana 1

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