Chemistry - March 2007

When we buy Magnesium, it is always covered with some black coating. What is that black thing? Is that Magnesium oxide? But magnesium oxide should be white.

2007-03-18 23:00:37 · 1 answers · asked by Anonymous

In a small school lab.
txs

2007-03-18 22:54:50 · 5 answers · asked by well.theres.a.few 6

2007-03-18 22:45:10 · 3 answers · asked by tikki 2

do I take 1ml of the 1 molar solution and dilute in 1000 mls of water again and so on for 0.2m, 0.3m etc ? Any help appreciated thanks

2007-03-18 22:43:49 · 4 answers · asked by louise faz 1

2007-03-18 22:22:47 · 3 answers · asked by †Jay 1

2007-03-18 22:16:26 · 2 answers · asked by Anand D 1

The specific heat of lead metal is .127 J/g *C. How many joules of heat would be required to raise the temperature of a 5.00g sample from 25*C to 35*C?

Can somebody please help me with this?

2007-03-18 21:52:24 · 2 answers · asked by keenan93312 1

http://i175.photobucket.com/albums/w153/Dexter47/100_0269.jpg

2007-03-18 21:50:18 · 3 answers · asked by dex4774 1

2007-03-18 21:49:53 · 3 answers · asked by Joesph P 1

If you have the biography, you can include it.

2007-03-18 21:20:18 · 3 answers · asked by nisa_mickey21 1

calculate:
#1) number of atoms in 2.0mol of sodium atoms

#2) molecules in 0.10 mol of nitrogen molecules

#3) atoms in 20.0 mol of carbon atoms

#4) molecules in 4.2 mol of water molecules

#5) atoms in 1.0 x 10^-2 mol of iron atoms

#6) molecules in 4.62 x 10^-5 of COv2
molecules

2007-03-18 21:17:27 · 5 answers · asked by Anonymous

the high temperature of engines cause the nitrogen&oxygen in air to react to form nitrogen monoxide( a reaction that plays a role in the formation of smog) ?

2007-03-18 21:15:50 · 4 answers · asked by kevin n 1

A bomb calorimeter whose components have a heat capacity of 6.66 kJ/°C is filled with 943 g of water. The initial temperature of the calorimeter contents is 21.61°C. A 1.144 g sample of benzoic acid (Ecomb = -26.42 kJ/g) is combusted in the calorimeter. What is the final temperature of the calorimeter contents?

2007-03-18 21:12:00 · 1 answers · asked by m0nk3y15 3

A gas mixture contains twice as many moles of O2 as N2. Addition of 0.200 mol of argon to this mixture increases the pressure from 0.800 atm to 1.10 atm. How many moles of O2 are in the mixture?

I don't even know how to setup the problem. Can somebody help me please!?

2007-03-18 21:11:45 · 1 answers · asked by keenan93312 1

List some examples, preferably with equations; much appreciated.

2007-03-18 20:50:52 · 5 answers · asked by Xaelia 5

2007-03-18 20:50:31 · 4 answers · asked by padmanaban b 1

i want to know for producing a thermacol sheet what types of material should we have?

2007-03-18 20:48:50 · 1 answers · asked by akhilesh_rajput07 1

2007-03-18 20:48:29 · 1 answers · asked by padmanaban b 1

The molar heat of vaporization of ethyl acetate, (CH3COOCH2CH3) is 32.5 KJ/mol. How much energy is required to vaporize 2.57 g of ethyl acetate?

I came up with 1113.0 KJ/mol, but I know that it's not right. Can someone please help me?

2007-03-18 20:45:30 · 2 answers · asked by keenan93312 1

2 O2

How many atoms of oxygen are represented by the above formula? (I think it's 2)

Can someone help explain how to tell how many molecules are in a formula?

-Thanks

2007-03-18 20:44:09 · 4 answers · asked by dex4774 1

Its for the research I'm doing. If you can help please help.

2007-03-18 20:43:25 · 3 answers · asked by Anonymous

2007-03-18 20:36:18 · 2 answers · asked by Ando 1

in chemistry

2007-03-18 20:36:13 · 27 answers · asked by amita sai 1

2007-03-18 20:15:29 · 7 answers · asked by euza12345 1

what are the empirical and molecular formulas for a compound that is 58.84% barium 13.74% sulfur and the rest oxygen, and a molar mass of 233.39 g/mol?

2007-03-18 20:07:50 · 2 answers · asked by kevin 1

And write out what it stands for .
e.g. CO2 : Carbon Dioxide : CO2
OK ?

2007-03-18 20:06:35 · 2 answers · asked by Anonymous

what is its empirical formula?

2007-03-18 20:00:38 · 2 answers · asked by kevin 1

2007-03-18 20:00:02 · 1 answers · asked by anindya b 1

2007-03-18 19:58:04 · 1 answers · asked by kevin 1

2007-03-18 19:54:42 · 4 answers · asked by kevin 1