Chemistry - November 2007

Please Help With the following Multiple Choice:

Which of the following is NOT a true description of gas behavior?
a) There is an inverse relationship between pressure and volume and for a fixed mass of gas confined at constant temperature
b) There is a linear relationship between temperature and volume at constant pressure
c) There is a linear relation between pressure and temperature at constant volume
d) For a fixed number of moles of a gas confined at constant temperature the product of pressure and volume is constant
e) The gas laws only describe correctly gas behaviors for pure gases and not mixtures of gases

14) Which gas law when extrapolated indicates that there is a minimum low temperature that nothing can be colder than?
a) Boyle’s Law
b) The constant volume law
c) The combined gas law
d) Charles’ Law
e) Avagadro’s Law

Any Help will be appreciated.
Thanx.

2007-11-15 09:13:26 · 1 answers · asked by Anonymous

Please explain how you got this answer. Thank you so much!!!

2007-11-15 09:11:11 · 1 answers · asked by furikuri405 1

The mass of gas A in containerA is 0.34g and the mass of gas B in containerB is 0.48g
a.which gas sample has the most molecules present?explain
b. which gas sample has the largest average kinetic energy. explain.
c. which gas sample has the fastest average kinetic velocity? explain
d. how can the pressure in the 2 containers be equal to each other since the larger gas B molecules collide with the container walls more forcefully?

My answers: can someone please check me? if anyone can give me a better explanation than my vague ones, it would be appreciated!!
a) both gas samples have the same molecules because the two gases are at STP
b) They are equal in the average kinetic energy because the average kinetic energy is proportional to the temperature and they both are under the same temperature.
c) Gas A has the fastest average velocity because it has a smaller mass (any equation i can use to prove this?)
d) gas A collides with the wall more frequently

2007-11-15 09:09:40 · 1 answers · asked by chrysanthemum11220 2

which one of these is the strongest bases:

a) NH2 or NH3
b) ClO3 or ClO2
c) Cl3CCOO or Cl2HCCOO

pick one strongest bases from a b and c...plz help i cant seem to get it rite

2007-11-15 08:49:07 · 2 answers · asked by Anonymous

i have electricity class and have problem answering these questions please help me the chapter were on is Sources of electricity , Chemical Energy


1) By generating electricity through the use of chemicals and their reation with other material - You have created _____________


2) The simple ______________ is a good example of chemical energy production.

3) _______________ material , in a cell provides a path for electricity .

4)the chemical inside a dry cell react with the _____________
and the carbon rob to produce electricity.

5)_____________ lights are a common application of dry cell .

2007-11-15 08:46:28 · 2 answers · asked by sweethoney9079 4

Elemental ananalysis of a compound results in the following data

40.00 % C

6.71 % H

53.28 % O



3.60 g of the compound fills a 190.0 ml bottle with a pressure of 3871.1 mm Hg at a temperature of 21.7oC. What is the molecular formula of this compound ?

2007-11-15 08:08:55 · 2 answers · asked by sovietwarhawk 1

2007-11-15 07:55:21 · 3 answers · asked by Anonymous

The standard heat of formation of CaBr2 is -675 . The first ionization energy of Ca is 590 and its second ionization energy is 1145 . The heat of sublimation of Ca is 178 . The bond energy of Br2 is 193 , the heat of vaporization of Br2 is 31 , and the electron affinity of Br is -325 .

2007-11-15 07:41:57 · 5 answers · asked by Suker 1

Cu(s) + AgNO3 (aq) --> Cu(NO3) (aq) + [ ]

2007-11-15 07:40:42 · 1 answers · asked by Margaret T 1

why does the colour of Co^2+ in aq. solution change on adding HCL?

why does colour of Fe^3+ change in presence of NCS-?

2007-11-15 07:34:16 · 1 answers · asked by Anonymous

2007-11-15 07:33:32 · 1 answers · asked by funvonne 2

Evaluate the effectiveness of each:

Gravity filtration (paper and sand/gravel)
Charcoal filtration
Centrifuging
Distillation

2007-11-15 07:26:32 · 2 answers · asked by Anonymous

2007-11-15 07:23:09 · 3 answers · asked by Anonymous

I need to write and balance the equation.

2007-11-15 07:21:26 · 3 answers · asked by John Smith 2

all non-metallic compounds and draw
the molecular model for any metallic compounds. Tell what kinds of bonds form (pure covalent, polar
covalent, ionic, or metallic), and indicate whether or not there is a resonance hybrid.

CIF3
NO3-1
Ca
MgO
F2

I have no problem with NO3-1, F2, or ClF3.

But I can't figure out what to do with MgO at all, and before I get all the people yelling at me, yes I have been through my text book and everything I can find on the web.

My other issue is Ca. Isn't Ca an atom and not a compound? If it is a compound how does that work?

2007-11-15 07:14:46 · 3 answers · asked by Emmy 1

AgNO3 +I- ->

HNO3 + Co3^2- ->

could someone please try explain how u do this?

2007-11-15 07:13:35 · 2 answers · asked by Anonymous

Balance this equation:
AgNO3 + Cu -> Cu(NO3)2 +Ag

What type of reaction is this? Why?

How many moles of silver could be produced by reaction of 3.5 moles of copper?

How many grams of silver could be produced by reaction of 3.5 moles copper?

How many atoms of silver could be produced by reaction of 3.5 moles of copper?

How many grams of silver could be produced by reaction of 10.0 grams copper with 50.0 g silver nitrate?

Which reactant is the limiting reactant?

Thanks in advance!
Btw, please explain this as clearly as possible!

2007-11-15 07:01:28 · 2 answers · asked by Anonymous

Sodium chloride decomposes into metallic sodium and chlorine gas.

The correct answer for the chemical equation for this reaction is 2NaCl--->2Na + Cl2

Could somebody please explain how this answer is reached? It didnt say anywhere that there were 2 atoms of NaCl and I am wondering where the 2 came from.
Thank you!

2007-11-15 06:47:50 · 3 answers · asked by Jada 1

Sodium hypochlorite: NaOCl

Should there be parenthesis around OCl, or do I have it right?

2007-11-15 06:46:00 · 2 answers · asked by isabelle.the.insomniac 2

2007-11-15 06:18:19 · 1 answers · asked by Anonymous

How do you find the answer to this question? Also, my teacher is really concerned with the class learning how to write problems like this out in parentheses....how do I do this??

2007-11-15 06:12:42 · 2 answers · asked by Anonymous

2007-11-15 06:06:51 · 4 answers · asked by Anonymous

can you specify in what you say? please

2007-11-15 06:02:42 · 4 answers · asked by Jac 1

1. Some cooking oils contain both saturated and unsaturated fats. The amount of unsaturated fat is determined by the iodine number of the fat mixture. Saturated fat has a iodine number of 0 – 2. Unsaturated fats may have iodine numbers of 50 – 100. What property of unsaturated fats allows for a high iodine number?

2. Soap is the sodium salt of a fatty acid. Millions of bars of soap are produced every year in the USA. Where do soap manufacturers obtain fats for the manufacture of soap?

2007-11-15 05:47:35 · 1 answers · asked by shashank 2

i know the basics like electrons,neutrons, and protons and stuff. but i wanna know the others. if you could tell me even just one or website where i could find them, that would be great!

2007-11-15 05:44:12 · 1 answers · asked by Ne-ne 1

How much heat is released when a mixture containing 24.7 g of CS2 and 100.0 g Cl2 reacts by the following equation

CS2(g) + 3Cl2(g) S2Cl2(g) + CCl4(g); ΔH = -230. kJ

2007-11-15 05:43:45 · 2 answers · asked by Bernie 1

hi i need a lot of help. I need to find the molar absorptivity of yellow dye. A 1.50 x 10^-5 M solution of this dya has an absorbance of .209 at its (wavelength sign)max. The path length is 1.0cm can anyone explain to me how to find the molar absorptivity? Step by step if possible. THANKS!

2007-11-15 05:10:11 · 2 answers · asked by Anonymous

1. Determine the molar solubility of PbI2. The Ksp values for PbI2 is 8.7 x 10^-9.

2. Determine the molar solubility of 100 mL of a solution of PbI2 to which 0.01 mole of lead nitrate, Pb(NO3)2 has been added. Assume the total volume remains at 100 mL.

3. The Ksp valu for calcium carbonate is 4.5 x 10^-9. Calculate the solubility of calcium carbonate in g/L.

If you could explain the steps I would really appreciate it so I can figure out the others on my own.

2007-11-15 05:00:13 · 4 answers · asked by eac 2

mass of copper : 1g
mass of hydrated sample: 2g
mass of dehydrated sample: 0.5 g
mass of water evolved: .01
moles of chlorine: 0.6

2007-11-15 03:52:48 · 1 answers · asked by mohjd s 1

If lead has an electron configuration of 2, 8, 18, 32, 18, 4. would that mean lead has 32 protons...or am I doing this wrong? thanks!

2007-11-15 03:42:46 · 1 answers · asked by lolliepop 2