Chemistry - June 2007

2007-06-05 07:22:11 · 6 answers · asked by hillio m 1

2007-06-05 07:20:48 · 3 answers · asked by hillio m 1

2007-06-05 07:17:24 · 4 answers · asked by hillio m 1

2007-06-05 07:11:45 · 5 answers · asked by hillio m 1

thanks

2007-06-05 07:09:25 · 3 answers · asked by hillio m 1

Mostly I need to know about Se. I'm debating whether it is molecular or covalent. I'm leaning toward covalent but the melting point of Se seems to be uncharacteristically low for a covalent solid. Molecular would better fit in that aspect but Se, the way it is presented in the question, isn't a molecule.

2007-06-05 07:01:25 · 4 answers · asked by Linduh. 3

I had some difficulty paying attention in chemistry today; the first question on the homework is:
"A closed manometer connected to a container of nitrogen has a height difference of 720mm in the two arms. What is the pressure of the nitrogen in the atmospheres?" how do you solve this? I remember she mentioned there was a difference between an open and closed manometer and she had two drawings. Thank you so much for any help.

2007-06-05 07:01:09 · 2 answers · asked by Adam S 2

When a paper is burning on a ceramic surface (like a plate) there is a yellow precipitation.
Can anybody, explain, please, what is it, what is the chemical reaction between it and the composition of this precipitation?

2007-06-05 07:00:58 · 1 answers · asked by Lex 1

I've heard that there is an experiment dealing with steel wool and vinegar and that the temperature increases... but by how much?
Just curious.
Please cite your sources.

2007-06-05 06:56:48 · 1 answers · asked by Anonymous

Does anyone know where sugar falls on the pH scale?! or any other experiments I can do to prove that a substance i have is sugar? PlEaSe!!??!

2007-06-05 06:51:33 · 4 answers · asked by Kelly O 2

2007-06-05 06:48:33 · 1 answers · asked by kedly L 1

2007-06-05 06:43:41 · 6 answers · asked by Riya M 1

find the formula reaction in solution, Molecular form, Total ionic, and Net ionic

2007-06-05 06:43:36 · 1 answers · asked by kedly L 1

I know petrolium ether is a mixure of several compounds, I just can't find any data on it.

2007-06-05 06:36:27 · 3 answers · asked by Anonymous

Can you walk me through this problem?

2007-06-05 06:29:27 · 9 answers · asked by ♥chloe♥ 2

According to molecular orbital theory, which of the following lists ranks the nitrogen species in terms of increasing bond order?

a.N22- < N2- < N2
b.N2 < N22- < N2-
c.N2 < N2- < N22-
d.N2- < N2 < N22-
e.N2- < N22- < N2

2007-06-05 06:07:41 · 3 answers · asked by Anonymous

What role did knowledge of Chargaff's rules play in the discovery of the DNA double helix? Please help me!!!!!

2007-06-05 06:07:04 · 2 answers · asked by taylor17brown 1

Refer to Molecular Orbital Theory. Consider the molecules Be2, B2, C2, and F2. Which two molecules have the same bond order?

a.Be2 and C2
b.B2 and F2
c.Be2 and B2
d.C2 and F2
e.B2 and C2

2007-06-05 06:06:10 · 1 answers · asked by Anonymous

the structure and formation of carbon-based polymers

2007-06-05 06:02:56 · 2 answers · asked by Shelly 1

According to molecular orbital theory, which of the following species is least likely to exist?

a.F22+
b.H2-
c.B22+
d.Li2
e.C22-

2007-06-05 05:48:49 · 1 answers · asked by Anonymous

According to molecular orbital theory, which of the following species is the most likely to exist?

a.Li22-
b.Be2
c.H22-
d.Li2
e.He2

2007-06-05 05:48:11 · 1 answers · asked by Anonymous

In which of the following molecules and ions does the central atom have sp2 hybridization: BF3, NO2-, NH2-, H2O?

a.NO2- and H2O
b.BF3 and NH2-
c.BF3 and NO2-
d.NO2- and NH2-
e.NH2- and H2O

2007-06-05 05:39:50 · 0 answers · asked by Anonymous

2007-06-05 04:10:09 · 3 answers · asked by Anonymous

Write the balanced equation for methanol (CH3OH) and oxygen (O2) reacting to produce carbon dioxide (CO2) and water (H2O) and determine the number of moles of oxygen that react completely with 4 moles of methanol.

2007-06-05 04:00:51 · 4 answers · asked by hamncheeser 2

2007-06-05 03:46:28 · 4 answers · asked by Anonymous

a. the movement of electrons
b. the "disappearance" of a small amount of mass.
c. the "creation" of a small amount of mass.
d. the breaking of bonds.

2007-06-05 03:04:43 · 9 answers · asked by DawnLynn 1

The mass of 6,022x10^20 Molecules og H2SO4 is:

I suppose 98 x 10^-3

Correct is 98mg. That must be wrong in my opinion!

2007-06-05 02:46:31 · 7 answers · asked by Anonymous

my book and internet say opposite things.

I would think alkaline.. because hydrogen is given off...

2007-06-05 02:42:14 · 14 answers · asked by cinnamonstar123 2

Relationship between the [H+], the [OH-], and pH

Acidity/Basicity
(Indicate areas of strong acids, strong bases, weak acids, weak bases and neutrality) [H+]

1.(mol/L) 2. pH 3.Aqueous system 4.(mol/L)
(example solution)
fill in two more acids,
one neutral two or three
bases [OH-]

Neutrality 1 x 10(0)
0 1 x 10(0) 1 M hydrochloric acid 1 x 10-14
1
2
3
4
5
6
7
8
9
10
11
12
13
14


I need the missing answers filled in from 1-14 the same way its written for the example given ( 0 )

THANKS!!!!!!!!!!!

2007-06-05 02:19:27 · 1 answers · asked by peek-a-boo 1

Aluminum metal melts at 660 Celsius and boils at 2450 Celsius. Its density is 2.70 grams/cc.

Calculate the following:
A.) Assuming an ideal gas, the volume occupied by 20 kilograms of aluminum vapor at its boiling points and under pressure of 2280 torr.
B.) The volume occupied by 1000 kilograms of the metal at 25 Celsius.
C.) If the specific heat capacity of aluminum metal is 0.89 Joules per gram-degree C, how many calories of energy are required to heat 10 kilomoles of aluminum from 250 Celsius to 500 Celsius.
D.) If 13.5 grams of aluminum were dissolved in an excess of concentrated HCL, what volume of hydrogen gas would be released at STP? You may assume that the ideal gas law holds and that the vapor pressure of water of water is negligible compared to the pressure of the released hydrogen.

2007-06-05 02:18:34 · 1 answers · asked by Reed 1