WorksheetsRandom Redox Q
Total questions: 7
Worksheet time: 35mins
Name
Class
Date
1.
The equation for the combustion of hydrogen is
2H2(g)+O2(g)→2H2O(g);
ΔH=-484 kJ/mol
The energy released when 2.40 g of hydrogen reacts is
2H2(g)+O2(g)→2H2O(g);
ΔH=-484 kJ/mol
The energy released when 2.40 g of hydrogen reacts is
a)
145 J
b)
290 J
c)
145 kJ
d)
290 kJ
2.
Consider the energy profile for a particular reaction.
Which of the following is an INCORRECT conclusion from the data presented?
Which of the following is an INCORRECT conclusion from the data presented?
a)
It takes more energy to break the bonds in the reactants than the energy released when the products form
b)
The activation energy of the reverse reaction is x+y
c)
The magnitude of the heat of reaction is equal to z-x
d)
When the products form, after bonds in the reactants are broken, energy equivalent to x+y-z is released.
3.
An electric current is passed through a solution of 1.0 M KCl. The reaction will occur at the cathode is
a)
K+(aq) + e- →K(s)
b)
2H2O(l) + 2e- →H2(g) + 2OH-(aq)
c)
2Cl-(aq)→Cl2(g) + 2e-
d)
2H2O(l)→ O2(g) + 4H+(aq) + 4e-
4.
An electroplating cell is devised to place a gold coating on a brass ring. A voltage of 2.80 V and a current of 1.35 A are passed through a solution of 1.00 M Au+ ions, for 280 seconds. The mass of gold produced, in grams, is closest to
a)
0.0129
b)
0.386
c)
0.772
d)
2.16
5.
Electrodes are placed in an aqueous solution of copper bromide and the power supply switched on. A current of 2.0 amp flows for 48250 seconds. The number of mole of copper that will be deposited at the ANODE in this cell will be
a)
0
b)
0.5
c)
1.0
d)
2.0
6.
Consider the electrolytic cell shown.
When an electric current is passed through the cell, at 25oC, the solution around the (+) electrode changes from green to yellow. This suggests the compound XY was most likely
When an electric current is passed through the cell, at 25oC, the solution around the (+) electrode changes from green to yellow. This suggests the compound XY was most likely
a)
sodium iodide
b)
potassium fluoride
c)
lithium bromide
d)
hydrochloric acid
7.
The electrolytic cell shown is used to extract metals from aqueous solutions of their nitrate salts.
If a current of 15.0 A is passed through the cell for 24.0 minutes, from which of the following solutions would the smallest amount of metal be deposited?
If a current of 15.0 A is passed through the cell for 24.0 minutes, from which of the following solutions would the smallest amount of metal be deposited?
a)
Co(NO3)2(aq)
b)
AgNO3(aq)
c)
Ni(NO3)2(aq)
d)
LiNO3(aq)
100 %
