Video Transcript
In the diagram shown, which
electrode is on the right? (A) The anode, as it is attracting
a cation. (B) The cathode, as it is
attracting a cation. (C) The anode, as it is attracting
an anion. (D) The cathode, as it is
attracting an anion.
In this diagram, we see two
electrodes that have been placed into the same beaker. This is an example of an
electrolytic cell, an electrochemical cell that uses electrical energy to drive a
nonspontaneous chemical reaction. Electrolytic cells are used for
electrolysis, a type of process where electrical current is passed through a liquid,
which causes the substances inside to decompose.
To sustain an electrolytic
reaction, we need to be able to continuously get power from a direct current power
source, an electrical cell, or a battery. In this notation, the longer line
represents the positive terminal of an electrical cell and the shorter line
represents the negative terminal. So the electrode on the right is
negative and the electrode on the left is positive.
In the cell, positively charged
ions called cations are attracted to the negative electrode, which we call the
cathode. Negatively charged ions called
anions are attracted to the positive electrode, which we call the anode. So, in this diagram, the anode is
on the left and the cathode is on the right.
In the diagram, we can see that
positively charged cations are being drawn towards the cathode and negatively
charged anions are being drawn towards the anode. In conclusion, the electrode that
is on the right is the cathode, as it is attracting a cation, answer choice (B).