- Which has the incorrect name-formula combination?
A) Sulfur dioxide -SO
B) lodine trifluoride – IF
C) Nitrogen tribromide – NBr.
D) Silicon tetrafluoride – SIF 4 - Describe the electrodes in this zinc-copper galvanic cell
Zinc Copper
List the following to either Zinc or Copper, anode, cathode, gains mass, loses mass
The Correct Answer and Explanation is :
1. Incorrect Name-Formula Combination:
The correct answer is A) Sulfur dioxide – SO.
Explanation:
- Sulfur dioxide (SO₂) is a molecule that consists of one sulfur (S) atom and two oxygen (O) atoms, not one oxygen atom (SO). Therefore, the formula SO is incorrect for sulfur dioxide. The correct formula for sulfur dioxide is SO₂.
- Iodine trifluoride (IF₃) correctly represents iodine bonded with three fluorine atoms.
- Nitrogen tribromide (NBr₃) correctly represents nitrogen bonded with three bromine atoms.
- Silicon tetrafluoride (SiF₄) correctly represents silicon bonded with four fluorine atoms.
2. Zinc-Copper Galvanic Cell Explanation:
In a zinc-copper galvanic cell, zinc and copper serve as the electrodes for the cell. Here’s the breakdown:
- Zinc Electrode (Anode):
- Zinc is the anode of the cell. In this part of the cell, zinc undergoes oxidation, meaning it loses electrons. The zinc metal dissolves into the electrolyte as Zn²⁺ ions.
- The loss of zinc metal causes the zinc electrode to lose mass because zinc atoms are turning into zinc ions (Zn²⁺).
- The reaction at the zinc electrode is:
[
\text{Zn (s)} \rightarrow \text{Zn}^{2+} (aq) + 2e^-
] - The electrons released during the oxidation process flow through the external circuit to the copper electrode.
- Copper Electrode (Cathode):
- The copper is the cathode in this galvanic cell. At this electrode, reduction occurs as copper ions (Cu²⁺) in the electrolyte gain electrons to form copper metal.
- The copper electrode gains mass because copper ions are reduced to solid copper, which plates onto the electrode.
- The reaction at the copper electrode is:
[
\text{Cu}^{2+} (aq) + 2e^- \rightarrow \text{Cu (s)}
]
Overall Process:
- The zinc electrode loses mass (oxidation), and the copper electrode gains mass (reduction).
- The galvanic cell generates an electric current because of the flow of electrons from the zinc anode to the copper cathode through the external circuit.
- This type of cell is spontaneous, meaning it generates electrical energy as a result of the chemical reactions occurring at the two electrodes.