|
Author
|
Message
|
![[Post New]](/templates/default/images/icon_minipost_new.gif)
31 Dec 2007 11:04:12 IST
|
|
|
A space shuttle is filled with Neon Gas at 1.00 atm and 290 K. The gas effuses through a pinhole in outer space at such a rate that the pressure drops by 0.30 torr/s .
(a)If the capsule were filled with ammonia at the same temperature and pressure, what would be the rate of pressure drop?
(b)If the capsule were filled with 30.0mol%HELIUM, 20 mol% OXYGEN and 50.0mol% Nitrogen at a total pressure of 1.00 atm and a temperature of 290 K what would be the corresponding rate of pressure drop?
|
SiNcY... |
this reply:
15 points
(with 3
in
3
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 12:36:11 IST
|
|
|
Which of the following statements best describes the spontaneity of a reaction at 25oC for which  Ssys is negative and Ssurr is positive? - The reaction will only be spontaneous if the change in free energy for the system is positive.
- The reaction will be spontaneous at all temperatures.
- The reaction will be spontaneous only if Ssys is greater in magnitude than Ssurr.
- The reaction will be spontaneous only if Ssurr is greater in magnitude than Ssys.
- The reaction cannot be spontaneous at 25oC.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
 |
this reply:
10 points
(with 2
in
2
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 12:37:18 IST
|
|
|
A sample of He(g) is placed in a 1.0-L flask at 298 K. The sample of He(g) is then heated to 450 K at constant volume. Microscopic "snapshots" for the He(g) are shown below.  S sys for this process is: - positive.
- negative.
- equal to zero.
- It is impossible to tell.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 12:39:38 IST
|
|
|
- For a particular chemical reaction, Ho is positive and So is negative. Which of the following statements about the spontaneity of the reaction under standard conditions is TRUE ?
- The reaction will be spontaneous only if the magnitude of Ho is large enough to overcome the unfavorable entropy change.
- The reaction will be spontaneous only if the magnitude of So is large enough to overcome the unfavorable enthalpy change.
- The reaction will be spontaneous regardless of the magnitudes of Ho and So.
- The reaction cannot be spontaneous.
- The reaction will be spontaneous only of Go is positive.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 12:40:34 IST
|
|
|
You built electrochemical cells as shown in the diagram below. The part of the experimental setup that functioned as a salt bridge is the:  - voltmeter.
- metal anode.
- beaker.
- metal cathode.
- ceramic disk in the crucible.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
2 points
(with 0
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 12:41:34 IST
|
|
|
If 10 mL a 1.0 x 10-4 M solution of a strong acid were added to 100 mL each of one solution containing 1.8 x 10-5 M hydrochloric acid and a second solution containing 1.0 M acetic acid (Ka = 1.8 x 10-5) plus 1.0 M sodium acetate, it is expected that the: - pH of both solutions would remain unchanged.
- change in pH would be very large in both solutions.
- change in pH would be the same in both solutions.
- change in pH would be larger in the solution containing acetic acid and sodium acetate.
- change in pH would be larger in the HCl solution.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
2 points
(with 0
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 14:26:52 IST
|
|
|
IIT-2000 A hydrogenation reaction is carried out at 500K.If the same rxn is carried out in the presence of a catalyst at the same rate,the temp. reqd is 400K.Calculate the activation energy of the rxn if the catalyst lowers the activation barrier by 20KJ/mol.
|
<TABLE CELLSPACING="1" CELLPADDING="1" BORDER="0">
<TR><TD>
<DIV ALIGN="right">Glitter Graphics</DIV></TD></TR></TABLE>
|
this reply:
10 points
(with 2
in
2
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 21:53:32 IST
|
|
|
What is the relationship between the following two square-planar compounds? The compounds are:  - linkage isomers
- optical isomers
- coordination isomers
- geometric isomers
- the same
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 21:56:01 IST
|
|
|
The quantity of a gas that will dissolve in a liquid is: - directly proportional to temperature.
- directly proportional to pressure.
- inversely proportional to pressure.
- independent of both temperature and pressure.
- none of the above.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
2 points
(with 0
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 21:57:03 IST
|
|
|
The vapor pressure of a volatile solute over a solution is: - proportional to the vapor pressure of the pure solute and the mole fraction of solute in the solution.
- proportional to the vapor pressure of the pure solute and inversely proportional to the mole fraction of the solute.
- inversely proportional to both the vapor pressure of the pure solute and the mole fraction of the solute.
- dependent only on the temperature of the solution.
- the same for all concentrations of the solute.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
2 points
(with 0
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 21:57:59 IST
|
|
|
Acetaminophen is found in some pain relievers. The structure of acetaminophen is shown below.  What is the molecular formula for acetaminophen? - C6H6NO
- C7H6NO2
- C8H9NO2
- C9H11NO2
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 21:58:41 IST
|
|
|
In visible spectroscopy, the wavelength at maximum absorbance (lambdamax) is usually used for a spectrophotometric analysis because: - chemical substances only absorb visible light at a single wavelength, lambdamax.
- the change in absorbance per unit change in concentration is largest at this wavelength.
- the change in absorbance per unit change in concentration is smallest at this wavelength.
- chemical substances absorb visible light equally well at all wavelengths.
- None of these.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
31 Dec 2007 22:00:18 IST
|
|
|
Which one of the following diagrams best illustrates the microscopic representation for the HALF-EQUIVALENCE POINT in a titration of a weak acid (HA) with sodium hydroxide (NaOH)? Note that water molecules are not shown for clarity. 
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
10 points
(with 2
in
2
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
2 Jan 2008 16:31:50 IST
|
|
|
A Currnet of 2 A is passing fr 5.00 h through a molten tin salt deposits 22.2g tin.
wht is the oxdn state of the tin salt ?
[Ans = 2+]
|
"your future depends on what u do in present"
|
this reply:
10 points
(with 2
in
2
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
2 Jan 2008 16:41:05 IST
|
|
|
how many hours will it take to produce 100 lb electrolytic chlorine frm NaCl in a cell tt carries 1000 A ? the anode efficiency fr the chlorine rxn is 85%.
[Ans = 40.3 hrs]
|
"your future depends on what u do in present"
|
this reply:
10 points
(with 2
in
2
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
2 Jan 2008 16:49:38 IST
|
|
|
Here is a matrix match problem>>>> Column 1 Column2 (a) A(s) = 3B(g) + C(G) (p) Kp/Kc < 1 (b) 2NO2(g) = N2O4(g) (q) N2 has no effect (c) N2H4(g) = N2(g) + 2H2(g) (r)Shift back on heating (d)S8 (s) = 8S(g) (s)Kp/Kx > 1 (Kx is eq constant in mole fraction)
|
Tarun Sharma
BITS - PILANI |
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
2 Jan 2008 16:50:40 IST
|
|
|
answer is>>>>
a----s,q
b----p,q,r
c----s
d----s,q
|
Tarun Sharma
BITS - PILANI |
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
4 Jan 2008 03:03:51 IST
|
|
|
whats the diffrence b/w banana bond and bridge bond.....wnt an elaborated ansr.......
sry frndz i dunno hav d soln...kindly hlp me!!!
|
PROGRESS ISN'T MADE BY EARLY RISERS OR HARD WORKERS, BUT BY LAZY PEOPLE TRYING TO FIND EASIER WAY TO DO THE SAME.....SO BE LAZZZZYY!!!! |
this reply:
0 points
(with 0
in
0
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
4 Jan 2008 22:33:01 IST
|
|
|
The electron configuration for nickel in the zero oxidation state is [Ar]4s23d8. Which of the following is the correct valence-bond representation of the complex ion, Ni(CN)4-2 ? Note: Unfilled circles represent two paired electrons from nickel and filled circles represent two paired electrons from the cyanide ion. 
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
7 points
(with 1
in
2
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
4 Jan 2008 22:33:31 IST
|
|
|
Which one of the following best explains why water is a monodentate ligand? - The oxygen atom in a water molecule only has one lone pair of electrons that it can use to form a coordinate covalent bond to a metal atom.
- Each hydrogen atom in a water molecule has only one electron with which to form a coordinate covalent bond to a metal atom.
- The oxygen atom in a water molecule has two lone pairs of electrons, but both pairs are used to form a single coordinate covalent bond to a metal atom.
- The oxygen atom in a water molecule has two lone pairs of electrons, but the second lone pair is not close enough to a second coordination site to form a coordinate covalent bond.
- None of these.
|
Ken
From: UNITED STATES, Green Bay, Wisconsin
|
this reply:
5 points
(with 1
in
1
votes
)
[?]
|
|
You have to be logged on to rate
|
|
|
|
|
Moderation Team
Community Discussion Question:
![[Up]](/templates/default/images/icon_up.gif "[Up]"){kind=icon}
