3. The diagram shows an electrochemical cell with a gold strip (left) and aluminum glasses (right).
In your response, do the following:
• Label the cathode and the anode, including the charge on each.
• Show the flow of electrons.
• Describe what type of electrochemical cell is pictured and what its use is.
• What are the oxidation and reduction half-reactions in this cell?
To label the cathode and anode in the diagram, you need to understand the principles of electrochemical cells. In an electrochemical cell, the cathode is the electrode where reduction occurs, while the anode is the electrode where oxidation occurs.
To determine the cathode and anode, you can consider the following:
1. Reduction occurs at the electrode that is gaining electrons, so it becomes positively charged.
2. Oxidation occurs at the electrode that is losing electrons, so it becomes negatively charged.
In the given diagram, the gold strip is on the left, and the aluminum glasses are on the right. Gold is less reactive than aluminum, indicating that aluminum will more readily lose electrons than gold. Therefore, the aluminum glasses will serve as the anode, and the gold strip will serve as the cathode.
Labeling:
- Anode: Aluminum glasses (right) with a negative charge, indicating oxidation.
- Cathode: Gold strip (left) with a positive charge, indicating reduction.
Next, let's describe the flow of electrons. Electrons flow from the anode (aluminum glasses) to the cathode (gold strip) in the external circuit. This flow of electrons generates an electric current that can be used for various applications.
Based on the diagram, the electrochemical cell is likely a galvanic or voltaic cell. These cells convert chemical energy into electrical energy. The purpose of such a cell is to produce a direct electric current.
Now, let's identify the oxidation and reduction half-reactions in this cell.
Oxidation half-reaction: Here, aluminum is oxidized and loses electrons at the anode. The corresponding oxidation half-reaction can be written as:
Al → Al3+ + 3e-
Reduction half-reaction: Gold ions from the cathode are reduced and gain electrons. The corresponding reduction half-reaction can be written as:
Au3+ + 3e- → Au
In summary, the given diagram represents an electrochemical cell where the aluminum glasses serve as the anode (oxidation) and the gold strip serves as the cathode (reduction). This type of electrochemical cell is likely a galvanic or voltaic cell that can produce an electric current by converting chemical energy into electrical energy. The oxidation half-reaction is the oxidation of aluminum (Al → Al3+ + 3e-), and the reduction half-reaction is the reduction of gold ions (Au3+ + 3e- → Au).