1
CHM151 Rio Salado Midterm Exam
Questions and Answers with detailes
rationales GRADED A+ GUARANTEED
PASS 100% Solved
Gold can be plated out one atom in thickness and look like solid gold. If a ring has a surface area
of about 6.45 cm^2 and if gold atoms can be packed 9.07x10^14 atoms/cm^2, how long would it
take using your home current of 15 amps to convert a metal ring into one that looked like solid
gold using Au^3+?
1.9x10^-4 seconds
.67 seconds
6.3x10^-5 seconds
.22 seconds –
ANS :1.9x10^-4 seconds
An electrolytic cell can be used to
generate electricity
store electricity
make a battery
electroplate an object that conducts electricity
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- ANS :ELECTROPLATE AN OBJECT THAT CONDUCTS ELECTRICITY
The waste product of a hydrogen fuel cell is
oxygen
electricity
carbon dioxide
water vapor –
ANS :WATER VAPOR
If a voltaic cell reaction is written in reverse, the
E becomes positive
deltaG become positive
reaction becomes spontaneous
E becomes zero –
ANS :deltaG BECOMES POSITIVE
What is E for a cell where E=1.10(Cu^2++Zn->Cu+Zn^2+),[Cu^2+]=1.50M and [Zn^2+]=.100M
atSATP?
1.03 V
1.13 V
1.02 V
1.18V
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- ANS :1.13 V
What is E for a concentration cell where [Ag^+]=.0012M in the diluted half-cell and 1.15M in the
more concentrated one at SATP?
-.41 V
.41 V
-.18 V
.18 V –
ANS :.18 V
Alkaline cells (batteries) typically contain manganese ions and solid zinc. Which of the following
must be correct?
the manganese gets reduced and zinc oxidized
the manganese and zinc both get reduced
the manganese and zinc both get oxidized
the manganese gets oxidized and zinc reduced –
ANS :THE MANGANESE GETS REDUCED AND ZINC OXIDIZED
In the electrolysis of molten sodium chloride
sodium is reduced
sodium is oxidized
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sodium is both oxidized and reduced
chloride is reduced –
ANS :SODIUM IS REDUCED
How many grams of nickel can be electroplated from Ni^2+ using 15amps for 2 hours?
33g
9.1x10^-3g
12kg
130g
- ANS :33g
Which of these is a radioactive particle?
microtron
negatron
megatron
positron
- ANS :POSITRON
Mo-99 undergoes beta emission to produce
Ru-99
Ru-100
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CHM151 Rio Salado Midterm Exam
Questions and Answers with detailes
rationales GRADED A+ GUARANTEED
PASS 100% Solved
Gold can be plated out one atom in thickness and look like solid gold. If a ring has a surface area
of about 6.45 cm^2 and if gold atoms can be packed 9.07x10^14 atoms/cm^2, how long would it
take using your home current of 15 amps to convert a metal ring into one that looked like solid
gold using Au^3+?
1.9x10^-4 seconds
.67 seconds
6.3x10^-5 seconds
.22 seconds –
ANS :1.9x10^-4 seconds
An electrolytic cell can be used to
generate electricity
store electricity
make a battery
electroplate an object that conducts electricity
1|Page
, 2
- ANS :ELECTROPLATE AN OBJECT THAT CONDUCTS ELECTRICITY
The waste product of a hydrogen fuel cell is
oxygen
electricity
carbon dioxide
water vapor –
ANS :WATER VAPOR
If a voltaic cell reaction is written in reverse, the
E becomes positive
deltaG become positive
reaction becomes spontaneous
E becomes zero –
ANS :deltaG BECOMES POSITIVE
What is E for a cell where E=1.10(Cu^2++Zn->Cu+Zn^2+),[Cu^2+]=1.50M and [Zn^2+]=.100M
atSATP?
1.03 V
1.13 V
1.02 V
1.18V
2|Page
, 3
- ANS :1.13 V
What is E for a concentration cell where [Ag^+]=.0012M in the diluted half-cell and 1.15M in the
more concentrated one at SATP?
-.41 V
.41 V
-.18 V
.18 V –
ANS :.18 V
Alkaline cells (batteries) typically contain manganese ions and solid zinc. Which of the following
must be correct?
the manganese gets reduced and zinc oxidized
the manganese and zinc both get reduced
the manganese and zinc both get oxidized
the manganese gets oxidized and zinc reduced –
ANS :THE MANGANESE GETS REDUCED AND ZINC OXIDIZED
In the electrolysis of molten sodium chloride
sodium is reduced
sodium is oxidized
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sodium is both oxidized and reduced
chloride is reduced –
ANS :SODIUM IS REDUCED
How many grams of nickel can be electroplated from Ni^2+ using 15amps for 2 hours?
33g
9.1x10^-3g
12kg
130g
- ANS :33g
Which of these is a radioactive particle?
microtron
negatron
megatron
positron
- ANS :POSITRON
Mo-99 undergoes beta emission to produce
Ru-99
Ru-100
4|Page
