When I am writing a half-reaction with a corroding metal that is in Deaerated water, what can i assume there to be in the water that can show up in a half-reaction?
When dealing with a corroding metal in deaerated water, you can assume that the primary species present in the water is just H2O (water molecules). Since the water is deaerated, it means that there is no dissolved oxygen (O2) or any other gas present in the water.
When writing a half-reaction, the focus is on the oxidation or reduction of the metal involved in the corrosion process. In this case, you would assume that the metal is being oxidized (losing electrons) since it is corroding.
To write the half-reaction, you can follow these steps:
1. Identify the metal that is corroding. For example, let's say it's iron (Fe).
2. Write the equation for the oxidation of the metal. In this case, iron is being oxidized, so it would lose electrons to form iron ions. The equation would be:
Fe(s) -> Fe2+(aq) + 2e-
This equation represents the half-reaction for the oxidation of iron in deaerated water.
Remember, in deaerated water, you do not need to consider the participation of any other species such as oxygen or other dissolved gases. The focus is primarily on the metal and its oxidation or reduction reaction.