12.
What balances charges that may build up as reduction and oxidation occur in a voltaic cell?
*the salt bridge
one of the half-cells
the electrolyte solutions
the moving electrons
13.
What is the electrode in the center of the most common dry cell made of?
copper
zinc
iron
*graphite
14.
How is a lead storage battery recharged?
*A direct current is applied to it.
A magnet is held close to it.
Alternating current is forced through it.
The pressure on it is increased.
15.
What happens in a hydrogen-oxygen fuel cell?
*Oxygen diffuses through the cathode.
Oxygen diffuses through the anode.
Hydrogen diffuses through the cathode.
Hydrogen and oxygen are mixed before entering the anode.
16.
What standard reduction electrode has a half-cell potential of 0.00 V?
oxygen
*hydrogen
lithium
fluorine
17.
Which of the following is the name of a process in which electrical energy causes a chemical reaction?
hydrolysis
*electrolysis
oxidation
electronation
18.
Which of the following is true about an electrolytic cell?
It changes electrical energy into chemical energy.
It is the type of cell used in electroplating.
It uses an electric current to make a nonspontaneous reaction go.
*all of the above
19.
Identify the products formed in the net reaction of the electrolysis of water.
liquid hydrogen and oxygen gas
liquid oxygen and hydrogen gas
*hydrogen gas and oxygen gas
aqueous hydrogen ion and hydroxyl ion
20.
What occurs in electroplating?
deposition of a salt layer on a metal
*deposition of a metal layer on a
material
decomposition of a metal layer
decomposition of a salt layer
Thank You.
12. I was tempted to pick the salt bridge, too, however, the salt bridge only ALLOWS the balancing charges to pass through is the proper direction. It's the electrolytes that actually do the balancing. Think about that for awhile. The question is somewhat ambiguous.
20. I agree with your answer; however, I should point out that in order for the metal to be deposited onto another surface, the metal must be "removed" from another place. Many might consider that a decomposition of the metal layer. Again somewhat ambiguous answer; I suspect your answer is the one desired.
All of the other answers look ok to me.
nnvcxc
For 12 it D all the rest are correct good job :)
12. The correct answer is the salt bridge. The salt bridge is a part of a voltaic cell that balances the charges that may build up as reduction and oxidation occur. It consists of an inverted U-tube filled with a salt solution, such as potassium chloride. The salt bridge allows for the flow of ions between the two half-cells, maintaining electrical neutrality.
13. The correct answer is graphite. The electrode in the center of the most common dry cell, also known as a zinc-carbon or alkaline battery, is made of graphite. Graphite acts as the cathode, where reduction reactions occur, during the discharge of the battery.
14. The correct answer is a direct current is applied to it. A lead storage battery, commonly used in vehicles, is recharged by applying a direct current (DC) to it. This reverse current causes the lead(IV) oxide (PbO2) and lead sulfate (PbSO4) in the positive and negative electrodes, respectively, to revert to their original forms, lead dioxide (PbO2) and lead (Pb). This recharging process allows the battery to be used again.
15. The correct answer is oxygen diffuses through the cathode. In a hydrogen-oxygen fuel cell, oxygen gas (O2) diffuses through the cathode, while hydrogen gas (H2) diffuses through the anode. At the cathode, oxygen combines with electrons and protons from the hydrogen to form water (H2O), releasing electrical energy in the process.
16. The correct answer is hydrogen. Hydrogen is the standard reduction electrode that has a half-cell potential of 0.00 V. This means that it is used as a reference point for measuring the potentials of other half-cells in electrochemical reactions.
17. The correct answer is electrolysis. Electrolysis is the name of the process in which electrical energy is used to cause a chemical reaction. It involves the passage of an electric current through an electrolyte, typically a solution, to drive a non-spontaneous redox reaction.
18. The correct answer is all of the above. An electrolytic cell changes electrical energy into chemical energy, it is the type of cell used in electroplating, and it uses an electric current to make a non-spontaneous reaction proceed. Electrolytic cells rely on an external power source to drive the reaction.
19. The correct answer is hydrogen gas and oxygen gas. In the net reaction of the electrolysis of water, the products formed are hydrogen gas (H2) and oxygen gas (O2). Water (H2O) is broken down into its constituent elements through the process of electrolysis, with the help of an electric current.
20. The correct answer is deposition of a metal layer on a material. Electroplating involves the process of depositing a metal layer onto a material, often to improve its appearance, protect it from corrosion, or alter its surface properties. This is achieved by passing an electric current through an electrolyte solution containing ions of the metal being deposited, allowing the metal ions to be reduced and form a thin, adherent layer on the material.