Chemistry - November 2007

It's 2 iodines bonded together by a truly non polar covalent bond.

2007-11-10 12:40:33 · 7 answers · asked by real 2

2007-11-10 12:25:24 · 1 answers · asked by adamarys c 1

2007-11-10 12:20:43 · 13 answers · asked by Anonymous

When aqueous silver nitrate and sodium
chromate solutions are mixed, solid silver chromate forms in a
solution of sodium nitrate. If 257.8 mL of a 0.0468 M solution of
silver nitrate is added to 156.00 mL of a 0.0950 M solution of
sodium chromate, what mass of silver chromate (M = 331.8 g/mol)
will be formed?
This is a limiting-reactant problem because the amounts
of two reactants are given.
Strategy:
(1) Write the balanced equation.
I have AgNO3 + Na2CrO4 --> Ag2 CrO4 + NaNo3
(2) Calculate the number of moles of each reactant.
.2578L x .0468M = .01207mols AgNO3
.156L x .0950M = .01482mols Na2CrO4
(3) Determine the limiting reactant.
AgNO3
(4) Calculate the moles of product.
.01482/.01207 = 1.228mol
(5) Convert moles of product to mass of the product using molar mass
1.228mol x 331.8g/mol = 407.4g Is this right? It seems like a lot.

2007-11-10 11:59:43 · 1 answers · asked by Heather L 1

2007-11-10 09:55:37 · 8 answers · asked by ighinee 1

http://wapsisquare.com/d/20071109.html
...shows a rather large diamond produced. Should it be this large? How many apples would be needed to produce a carat (not a carrot)?

2007-11-10 09:48:42 · 5 answers · asked by BotanyDave 5

Thanx!

2007-11-10 09:24:47 · 1 answers · asked by B9O9R9I9C9U9A 3

2007-11-10 09:13:14 · 4 answers · asked by Anonymous

Suppose you take some ice from the freezer, put it in a pan, and heat the pan gently on the stove until the ice melts. Is this a chemical or a physical change?

chemical

physical

2007-11-10 09:12:48 · 5 answers · asked by Anonymous

You have seen bubbles form inside the bottle when you open a soda bottle. Explain this phenomenon.

2007-11-10 09:11:25 · 4 answers · asked by Anonymous

2007-11-10 08:56:36 · 2 answers · asked by Anonymous

Which would probably have a mass of about 3 grams?

3 textbooks

3 baseballs

3 paper-clips

3 grains of sand

2007-11-10 08:52:38 · 7 answers · asked by Anonymous

can you explain to me why I3- is linear?

thank u very much

2007-11-10 08:13:30 · 3 answers · asked by Ganbatteru 3

Find the velocity of an electron emitted by a metal whose threshold frequency 2.10×10^14 s^-1, when it is exposed to visible light of wavelength 4.89×10^−7

I have been trying to figure this out for so long! can some one Please give me a hand?
Thank you

2007-11-10 07:43:25 · 2 answers · asked by anonymous 2

2007-11-10 07:10:43 · 5 answers · asked by Shadae 1

Al(NO3)3 + Ba(OH)2 ----> Al(OH)2 + Ba(NO3)3

2007-11-10 05:41:52 · 5 answers · asked by Emerson 5

2007-11-10 05:08:51 · 8 answers · asked by Anonymous

1) Why is group IIA very low in electron affinity?
2) Why is group VA very low in electron affinity?
3) Which has higher electron affinity?

A: Na or K
B: O or F
C: S or Cl
D: D or N
E: O or Se
F: Ca or Mg

2007-11-10 04:55:42 · 2 answers · asked by Lollipop 3

I've only got 5 tries left on this problem. Can anybody help me?

Consider the titration of 50.0 mL of 0.200 M HClO4 by 0.100 M NaOH.

Calculate the pH after 34.7 mL of NaOH has been added.

pH =

At what volume (in mL) of NaOH added does the pH of the resulting solution equal 7.00? Include the units of mL in your answer.

NaOH =

2007-11-10 04:01:21 · 1 answers · asked by Guinness 3

2007-11-10 03:34:09 · 1 answers · asked by Anonymous

2007-11-10 03:04:40 · 1 answers · asked by hannah_kf 3

1) given the following data:
2C (s) + O2 (g) ---> 2CO (g) delta H = - 222 kJ mol -1
2CO (g) + O2 (g) ----> 2CO2(g) delta H = -566 kJ mol -1
what is the standard enthalpy f combustion of carbon?

2)the standard enthalpy changes for the combustion of decane, octane and ethene are - 6778, -5470, -1411 kJ mol -1. use these data to calculate the standard enthalpy change for the cracking of decane :
C10H22(l) ----> C8H18 (l) + C2H4 (g)

2007-11-10 00:49:11 · 1 answers · asked by Anonymous

Calculate the standard enthalpy of formation of magnesium carbonate, using the following information. the standard enthalpy of combustion of magnesium is - 602 kJ mol -1 and that of carbon is - 394 kJ mol -1. the standard enthalpy change for the decomposition of magnesium carbonate in the reaction:
MgCO3 (s) ----> MgO (s) + CO2 (g)
is 100 kJ mol-1

2007-11-10 00:48:21 · 1 answers · asked by Anonymous

whay are the purposes of research?

2007-11-10 00:23:57 · 3 answers · asked by sheshe 1

while calculating the equilibrium constant for the reaction between hydrogen and iodine, how can we just assume that the concentrations of hydrogen and iodine at equilibrium are equal? does the initial concentration of hydrogen and iodine have to be equal in order for this to be true or are their eqm, concentrations equal in every case?

2007-11-10 00:00:11 · 2 answers · asked by amandac 3

2007-11-09 19:02:13 · 5 answers · asked by Anonymous

Thanks!

2007-11-09 18:45:47 · 2 answers · asked by Anita 5

2007-11-09 17:56:00 · 6 answers · asked by onetreehunny 4

I'm not sure if whoever wrote my chemistry text book just sucks at chemistry, or if they completely forgot to mention something. In reactions where a chemical catalyst is involved (i.e. CH4(g) + H2O(g) >>> nickel catalyst >>> CO(g) + 3H2), are you supposed to do something different to figure out delta H rather than just using "Delta H = sigma n delta H (products) - sigma n delta H (reactants)"?

Because for the question I mentioned above I keep getting delta H as 205.7 kJ, but the book says it is supposed to be 249.7 kJ.

This has happened to me with two questions in there involving chemical catalysts so far... Are the answers in my book just wrong?

Any help would be greatly appreciated.

2007-11-09 17:53:00 · 1 answers · asked by Anonymous

2007-11-09 17:14:55 · 4 answers · asked by Larissa 1