Chemistry - September 2007

F2
N2
NO+
CO
O2

Please explain to me why the answer is what it is

thanks

2007-09-25 06:05:55 · 1 answers · asked by ccutestuff2001 2

2007-09-25 06:02:12 · 3 answers · asked by ccutestuff2001 2

they're negative and nucleus is positive they're are supossed to atract. where am i wrong?

2007-09-25 05:35:15 · 4 answers · asked by Anonymous

isn't it supossed to repel each other?

2007-09-25 05:31:59 · 5 answers · asked by Anonymous

2007-09-25 05:25:28 · 2 answers · asked by Anonymous

What mass, in grams, of ZnCl2 can be prepared from the reaction of 3.27 grams of zinc with 3.30 grams of HCl? Zn + 2HCl → ZnCl2 + H2

2007-09-25 05:22:54 · 2 answers · asked by mike g 1

2007-09-25 04:15:38 · 5 answers · asked by shell 1

The medical thermometer commonly used in homes can be read +/-0.1 F, whereas those in the doctor's office may be accurate to +/- 0.1 C. in degrees Celsius, expres the percent error expected from each of these thermometers in measuring a person's body temperature of 38.9 C

2007-09-25 03:48:18 · 1 answers · asked by Anonymous

2007-09-25 03:19:38 · 5 answers · asked by stefan p 1

A mixture consisting of 11.3 g of calcium fluoride, CaF2, and 13.0 g of sulfuric acid, H2SO4, is heated to drive off hydrogen fluoride, HF.




CaF2(s) + H2SO4(l) ==> 2HF(g) + CaSO4(s)




What is the maximum number of grams of hydrogen fluoride that can be obtained?

2007-09-25 03:19:19 · 3 answers · asked by Joe C. 1

2007-09-25 00:37:35 · 5 answers · asked by Anonymous

dilute nitric acid is added to an unknown solution followed by barium chloride reagent.

2007-09-24 23:32:45 · 1 answers · asked by Anonymous

calculate the number of milliliters of .200 M Ba(NO3)2 which would be required to just precipitate all o fthe sulfate as barium sulfate

2007-09-24 22:12:44 · 4 answers · asked by Anonymous

I think this will become the basis of producing Hydrogen by using water. Is there someone who has done and experiment on Hydrogen fuel? I want to know a couple of things:
1) How much hydrogen do you need to create a fire?
(nothing fancy, just the amount that is needed to create a matchlike fire)
2) How much hydrogen can Chemalloy produce?
(I know Chemalloy can produce 0.5 V, but I couldn't find the hydrogen volume that it creates)
3) If you think chemalloy is not the solution, then what is?

Thx in advance.

2007-09-24 21:21:21 · 1 answers · asked by Arip 2

2007-09-24 21:17:24 · 9 answers · asked by Anonymous

my brother keeps telling me that the u.s has a is 200 Megaton bomb? i dont believe him

2007-09-24 20:50:24 · 3 answers · asked by c d.o.t 3

2007-09-24 20:37:08 · 1 answers · asked by lixingsddx 1

whats more powerful

2007-09-24 20:31:55 · 6 answers · asked by c d.o.t 3

-_-

2007-09-24 20:13:27 · 2 answers · asked by Anonymous

ELECTRON CONFIGURATION
Energy Level: 1 2 3
Electrons: 2 8 8

according to the peridoic table and the info above, which element has this electron configuration?

a) Sodium

b) Neon

c) Magnesium

d) Argon

2007-09-24 19:48:01 · 4 answers · asked by XOXO 1

2C2H2(g) + 5O29g0 → 4CO2(g) + ____

*all but the first "2" is suppose to be lowered.
example: H2O - the "2" is usually lower than the H and the O....make since?

a) 4OH(aq) **4 is NOT lowered

b) CH4(aq) **4 IS lowered

c) H2O2(g) ** both numbers lowered

d) 2H2O(g) **first "2" normal, second "2" lowered

2007-09-24 19:33:22 · 4 answers · asked by XOXO 1

2007-09-24 19:26:14 · 3 answers · asked by Anonymous

they...
a) have differences in reactivity

b) are able to bond with oxygen

c) vary in solubility

d) exist in different places

2007-09-24 19:25:00 · 2 answers · asked by XOXO 1

is carbon dioxide a triatomic molecule or a compound?
is ozone a triatomic or polyatomic molecule?i thought ozone had 3 oxygen atoms in it...

2007-09-24 19:20:39 · 3 answers · asked by Anonymous

its a baby bottle warmer in which you activate the bag by boiling, but after a feel hours or weeks later when the bag is even at room temp.when you need instant heat just click this little metal button inside and the clear gel or water inside starts turning like snow, but it's hot instanly like magic?
please explain

2007-09-24 19:18:02 · 1 answers · asked by marcos t 1

Calculating the Determination of Water in a Hydrate????HELP!!!?

Here are the weights:

Weight of crucible and cover = 12.85grams
Weight of crucible, cover and sample = 16.21grams
Weight of crucible, cover and sample after first heating = 14.82grams
Weight of crucible, cover and sample after second heating = 14.74grams
Weight of crucible, cover and sample after third heating = 14.72 grams

My chemistry teacher wants me to find the calculations of these samples above. I have no F'in idea if I am right or wrong when I am working out this problem.

I think the formula is Percentage of water=(mass lost divided by mass of sample) and then you multiply it by 100.

Here are the directions for the calculations:

Calculate weight of original sample
Numerical setup:


Calculate weight lost from sample by heating
Numerical setup:


Calculate percentage of water in sample
Numerical setup:


For this one, it also asks:

sample No._____
Percentage of water_____

2007-09-24 18:57:25 · 1 answers · asked by danie 2

120 torr and 210mm HG

a. 2275 torr
b. 972 torr
c. 0.411atm
d. 331 torr

2007-09-24 18:48:24 · 1 answers · asked by Anonymous

if you had used a crude balance that allowed only one signnificant figure, how would this have affected your results for a) area, b) volume,c) thickness

2007-09-24 18:44:32 · 1 answers · asked by Anonymous

Does anyone know how to calculate normality of the following aqeous solutions?
.25 M Na C2H3O2 (sodium acetate)

.50 M K2SO4 (potassium sulfate)

5.0% (w/v) CaCl2 (calcium chloride)

please help??? i need this one ! please

2007-09-24 18:34:06 · 3 answers · asked by SJ 1

The average density of the universe as a whole is estimated to be about 1.5*10^-29 g/cm^3. If we assume that the entire mass is only hydrogen atoms, what is the average volume of space, in liters that contains one H atom?

2007-09-24 18:24:35 · 2 answers · asked by Anonymous