Chemistry - October 2007

Chemical bonds are necessary to keep atoms together although their negative outer surfaces create a weak attraction between the atoms.

TRUE or FALSE

I think it is TRUE but the after the distractor part- after the "although" - is what is making me think that it is FALSE.

2007-10-15 03:56:59 · 1 answers · asked by LJC 2

I'm having trouble determing the products of anything reacting with heat. These are the 2 questions

What are the products?

Silver oxide + lots of heat ------>

and

Calcium carbonate + heat ---->

Thanks!

2007-10-15 03:40:10 · 3 answers · asked by Sandra 2

this question is based on Biochemistry

2007-10-15 02:47:21 · 3 answers · asked by Mlo 1

Calculate q when 0.10 g ice is cooled from -23°C to -75°C (cice = 2.087 J/g·K).

2007-10-15 01:55:37 · 3 answers · asked by jnester0289 1

A gas has volume of 20l measured at 27degreescelsius and 4 atmospheres. what will be its volume at STP?

2007-10-15 01:46:15 · 4 answers · asked by vivalagirl 2

I'm doing a scatterchart for my chemistry class and the data is .0500 and .0350, ect. I can't get excel to show the trailing zeros, it always cuts them off to .05 and .035. Anyone know how to make this program display the zeros? I went to help and it said to go to tools, options, view and uncheck the zero values box. It didn't work. Does anyone know how to do this? thanks

2007-10-15 01:03:45 · 10 answers · asked by Anonymous

Three 45g ice cubes at 0C are dropped into 5x10^2 mL of tea to make ice tea. The tea was initially at 20C; when thermal equilibrium was reached, the final temperature was 0C.

How much of the ice melted and how much remained floating in the beverage?
Assume the specific heat capacity of tea is the same as that of pure water

2007-10-14 22:10:39 · 2 answers · asked by beeboroachgoingon197 1

You should use care when dissolving H2SO4 in water because the process is highly exothermic. To measure the enthalphy change, 5.2g H2SO4 (l) was added (with stirring) to 135g of water in a coffee-cup calorimeter. This resulted in an increase in temperature from 20.2 degrees C to 28.8 C.

Calculate the enthalphy change for the process
H2SO4(l) -> H2SO4(aq), in kJ.mol.

2007-10-14 22:01:43 · 2 answers · asked by beeboroachgoingon197 1

2007-10-14 21:45:13 · 2 answers · asked by Anonymous

I need to find a place or store that sales potassium or sodium cyanide for mail order.

2007-10-14 18:26:53 · 3 answers · asked by Gene K 1

what is the hybridization of Cl in NH4Cl?

2007-10-14 18:11:18 · 1 answers · asked by Anonymous

C02 is 1
methane is quoted at 250-350
a lot of cfc's are quoted much higher

anyone know the multiplier for water vapor. i can not find it anywhere and a source if you can quote one would be appriciated

2007-10-14 18:00:19 · 2 answers · asked by j b 2

What is the net ionic and total ionic eqaution for

CH3COOH (acetic acid) and
NH3


thnx

2007-10-14 17:12:10 · 2 answers · asked by Anonymous

Hey,

I need help with writing the Ionic and Net Ionic equations for these:

1.)CH4 (g) + O2 (g) -----> CO2 (g) + H2O(l)
2.) Mg(s) + 2HOH(l) -----> H2(g) + Mg(OH)2 (aq)

The main reason why I am not getting these is because I am not sure if the gases break apart into ions when writing the Ionic equation. Ex:

CH4 (g)

Does that break apart into C (+/-4) (g) + 4H (g)

Thanks alot!!!!

2007-10-14 17:06:57 · 1 answers · asked by Ryan 3

Part one Heat of Solution:
If 4.436 g of NaOH was added to 150.0 mL of water
and we assume the density of water to be 1.000 g/mL
then what is the total mass? (Watch your Sig. Figs.)

If in part one, 4.436 g of NaOH was weighed out. How many moles of NaOH is this ?

Given that the temperature change observed was 11.5 C
when 4.436 g of NaOH were added to 150.0 mL of water.
What is the heat energy in kJ that is produced. (Don't
forget the specific heat of this SOLUTION is 4.06 j/ g C.)

Lets say that the heat produced when 4.436 g of NaOH was added to a water solution was 6.123 kJ. What is the calculated heat of solution (hint kJ/mole)?

These are some practice quiz problems Im having trouble with. Thanks.

2007-10-14 16:19:01 · 2 answers · asked by qwerty 2

a 100 L flask contains a mixture of CH4, and argon at 25 C, the mass of argon present is 228 g. and the mole fraction of methane in the mixture is 0.650. Calculate the total kinetic energy of the gaseous mixture.

How would you work this problem?

2007-10-14 16:01:47 · 1 answers · asked by sexxxxxxy4u 2

My eqaution was

(Mn^+2) + (NaBiO3) -> (Bi^+3) + (MnO4^-1)

if i were to balance this equation where would the Sodium go?
It does not have a Sodium on the other side. how would i balance this?
Please help.
Thank you.

2007-10-14 15:20:20 · 1 answers · asked by Jiwoo S 1

Consider a hypothetical species "HeH". What charge, if any, should be present on this combination of atoms to produce the most stable or ion possible?

1. None of these
2. -.5
3. +.5
4. -1
5. +1

If the charge on this species were increased or decreased by one, what would be the effect on the bond order in the molecule?

Choices: increase by .5, increase by 2, increase by 1, decrease by 1, decrease by .5

Which of the following species possesses a delocalized bond?

1. No molecule here
2. NO3-
3. NCl3
4. H2S
5. H2O

2007-10-14 15:10:13 · 1 answers · asked by beehappinow 1

is the partial pressure of oxygen(in torr)?

a. 35
b. 155.4
c. 585.2
d. 740.7
e. 352.6

2007-10-14 15:00:26 · 1 answers · asked by tessababy992006 1

A solution is prepared by dissolving 13.2 grams of Ba(OH)2* 8 H2O in 275 mL of aqueous solution. Ba(OH)2* 8 H2O is water soluble and is a strong electrolyte. Calculate the OH- (aq) concentration (molarity) in the resulting solution.

Please explain how you do it. Thank you.

2007-10-14 14:52:49 · 1 answers · asked by Anonymous

When 1.500 g of a metal oxide is heated, the compound decomposes in the reaction:

2X2O(s) ---> 4X(s) + O2(g)

If 0.1035 g O2 is produced, what is the identity of the unknown metal X?

2007-10-14 14:49:31 · 1 answers · asked by Guy B 1

Decomposition of ammonium carbonate...

is it:
(NH4)2CO3 --> NH4 + CO3
(NH4)2CO3 --> NH3 + CO2 + CO1
(NH4)2CO3 --> NH4 + CO2 + CO1
(NH4)2CO3 --> NH3 + CO3

***at the end of the reaction there was nothing left in the test tube*****

also are these aqueous: calcium hydroxide & hydroxide

2007-10-14 14:49:29 · 1 answers · asked by holaaloha12345 4

I tried to figure it out but keep getting the wrong answer if anyone out there can show me step by step how to solve this problem I would greatly appreciate it.

2007-10-14 14:47:19 · 1 answers · asked by Nikki C 1

2007-10-14 14:21:52 · 2 answers · asked by Luis V 2

2007-10-14 13:56:15 · 5 answers · asked by Chestudent 2

A system contracts from an initial volume of 15.0 L to a final volume of 10.0 L under a constant external pressure of 0.800 atm. The value of w, in J, is

2007-10-14 13:52:44 · 1 answers · asked by cpistone7 2

2007-10-14 13:43:05 · 1 answers · asked by cnfer657 1

I will be tested on this in 2 weeks so I am practicing.
For CO2 ,would the carbon be at either a +4 or a +2 because the oxygen is -2 or -1 or would the oxygen be a -4 or -2 because it is two oxygen molecules.

For Na2CO3 , the sodium is 1 x 2 = +2, the oxygen is 3 x -2 = -6 ,so the carbon would have to be +4 to balance it out?
THANKS

2007-10-14 13:39:33 · 1 answers · asked by Boo Radley 4

2007-10-14 13:28:47 · 2 answers · asked by lirael1019 1

are hydrocarbons held togther by ionic or hydrogen bonds? also, are they hydrophic? polar or non polar?

2007-10-14 13:23:10 · 5 answers · asked by noctem55 1