Software of the Month Club 1996 November/Software of the Month Club 1996 November.iso/pc/dos/edu/practice/mc1.dat

Text File | 1995-11-16 | 1.6 KB | 80 lines

1
The enthalpy of vaporization of
a liquid can be obtained from the
straight line obtained from which of
these plots ?
1)  vapor pressure vs. 1/T
2)  log vapor pressure vs. T
3)  log vapor pressure vs. 1/T
4)  vapor pressure vs. T
end
Type the number of the your response.
end
3
The Arrhenius equation relates vapor
pressure and temperature.
end
The Arrhenius equation is
log P2/log P1=(Hvap/2.3 R)(T2-T1/T2T1)
end
Since y=mx+b the slope of a log
vapor pressure vs. 1/T plot will equal
-Hvap\2.3 R
end
3
1
Which would you classify as a
semiconductor?
1) diamond
2) silicon
3) silver
4) sodium bromide
end
Type the number of the your response.
end
3
A semiconductor would conduct
electricity under some conditions and
not conduct under other conditions.
end
Metals conduct electricity, nonmetals
do not. Metalloids sometimes do and
sometimes do not.
end
Pick the only metalloid in the group
which is located on the "staircase"
on the periodic table.
end
2
1
In a simple first order reaction, the
half-life was found to be 15.0
minutes.  If the initial concentration
of the reactant was 0.200 M, what
is the concentration after 45.0
minutes?
end
1)  0.150 M
2)  0.100 M
3)  0.0667 M
4)  0.0500 M
5)  0.0250 M
Type the number of your response.
end
3
Half life is the time required for
one-half of a given substance to react.
Since the half life is 15.0 minutes
one half of the 0.200 M reactions
decays every 15 minutes.
end
Since the total time is 45.0 minutes
that means 3 half-lives have passed.
end
Divide 0.200 M by 2 three times.
0.200/2 = 0.100
0.100/2 = 0.050
0.050/2 = 0.025
end
5