Chemistry - January 2007

2007-01-16 04:47:41 · 6 answers · asked by muchacho_fresco 2

Rutherford theorized that atoms have a dense positive center or nucleus. How was the evidence for this conclusion illustrated in the animated gold-foil experiment?

2007-01-16 04:44:06 · 2 answers · asked by Amanda K 1

What are the tests that can be used?

2007-01-16 04:42:35 · 2 answers · asked by Dhanashri 2

2007-01-16 04:38:26 · 3 answers · asked by chaniquana 1

2007-01-16 04:37:36 · 4 answers · asked by colorado_usa_uk 1

does Hot water freeze faster than clod water? and if it does why? and if it doesn't what would lead someone to believe this?

2007-01-16 04:19:33 · 5 answers · asked by Petunia247 2

ok so i am carrying out a reaction that produces an immense amount of Hydrogen ions and that needs to be done at a pH of 6.8. I have two acids for preparing buffers. the first acid has a pka of 6.3 and the second acid has a pka of 7.3. which acid would make a better buffer? or would water just work fine as a buffer?

2007-01-16 04:14:57 · 2 answers · asked by Anonymous

2007-01-16 04:00:10 · 7 answers · asked by Anonymous

2007-01-16 03:46:05 · 2 answers · asked by Stacy 1

2007-01-16 03:41:48 · 4 answers · asked by Stacy 1

http://img242.imageshack.us/img242/1699/unbalancedequationvn0.png

2007-01-16 03:38:20 · 4 answers · asked by Stacy 1

I am on a question which says "Explain what happens when magnesium burns"! I need help and my science book is rubbish! Please help me!

2007-01-16 03:27:49 · 6 answers · asked by .:Tenten:. 1

Darkness is the absence of light.
I was wondering if there is any ( in chemistry, physics, biology) way to make darkness without absenting of light?

2007-01-16 02:46:19 · 5 answers · asked by Miear 1

2007-01-16 02:44:28 · 8 answers · asked by Anonymous

For the chemical reaction H2 + CO2 H2O + CO, the energy contained in the reactants is 352 kJ, and the energy contained in the products is 394 kJ, assuming 1 mol of each substance is present. Which of the following statements is true?

1.) 42 kJ is released, and the reaction is exothermic.
2.) 42 kJ is released, and the reaction is endothermic.
3.) 42 kJ is absorbed, and the reaction is exothermic.
4.) 42 kJ is absorbed, and the reaction is endothermic

2007-01-16 02:42:32 · 3 answers · asked by Anonymous

Everyone knows that hot air from a furnace is dry - that's why people buy humidifiers. But why? Shouldn't hot air retain more water vapor?

2007-01-16 02:35:40 · 7 answers · asked by ericesad 1

1 mole of CO(g) reacts with 1 mole of steam to form CO2(g) and hydrogen(g) in a 10L closed container. when equlibrium was reached, 40% of initial concentration of CO changed into products. Calculate the value of equlibrium constant.(show the method)

2007-01-16 02:33:04 · 1 answers · asked by iron muncher 3

1.) It lost electrons and was oxidized.
2.) It lost electrons and was reduced.
3.) It gained electrons and was oxidized.
4.) It gained electrons and was reduced

2007-01-16 02:31:51 · 4 answers · asked by Anonymous

When magnesium carbonate, MgCO2, reacts with nitric acid, HNO3, magnesium nitrate and carbonic acid form. Carbonic acid then breaks down into water and carbon dioxide. What two types of reactions take place in this process?

1.) synthesis and decomposition
2.) single-replacement and combustion
3.) double-replacement and decomposition
4.) double-replacement and combustion

2007-01-16 02:30:54 · 3 answers · asked by Anonymous

Hydrochloric acid, HCl, is added to solid NaOH. After the reaction is complete, NaCl dissolved in water remains. What are the products of this chemical reaction?

1.) NaOH and HCl
2.) NaOH and H2O
3.) HCl and NaCl
4.) NaCl and H2O

2007-01-16 02:27:01 · 3 answers · asked by Anonymous

all cooking receipe's seem to be for electric cookers and i use gas.

2007-01-16 02:19:03 · 2 answers · asked by Agnes B 2

2007-01-16 02:01:31 · 3 answers · asked by Chocolate Strawberries. 4

2007-01-16 02:00:34 · 24 answers · asked by shreenadeen a 1

2007-01-16 01:38:37 · 5 answers · asked by okiron 1

I do not drink.
I am not diabetic.
I take antabuse to rule out drinking for the court(monitored)

2007-01-16 01:00:52 · 3 answers · asked by elmer k 1

2007-01-16 00:32:12 · 6 answers · asked by divya 1

Finding mass of 1 atom given molar mass & density?

I) Given the density of something (e.g. platinum, aluminum) and the molar masses, how do you figure out the mass of an atom of each?

2) Then how do you find out how many atoms are in a meter^3

2007-01-16 00:24:08 · 2 answers · asked by ☆ 2

Rutherford said that electrons are moving and loss energy and get close to nucleus and falls in it and get collapse.But it is said to be wrong.What is wrong with it?Electromagnetic theory states that 'a moving charged particles radiate energy' . We also know that distance decrease with the decrease of energy.According to both of the laws,Rutherford's commment is right.Please tell me why,Ford's model is drawbacked?

IF YOU DON'T UNDERSTAND WHAT I AM TELLING?EPLY THAT I DIDN'T UNDERSTAND.THEN I WILL DESCRIBE MORE.OK.

2007-01-16 00:15:54 · 7 answers · asked by ukp15 2

i need to lower the pH of my solution to 4.5 but the pH is 10...how would i lower it

2007-01-15 23:39:02 · 9 answers · asked by Anonymous

can i find out if alcohol floats

2007-01-15 23:10:56 · 5 answers · asked by mageratorlongor 1