So i am asked to write the equation representing the third ionization energy for Cr, and what I could come up with is Cr^2+(g)->Cr^3+ + e(not sure if I am right).
For the second part I am told that the electron affinity of K is 48 kJ/mol, and i am supposed to write the equation for which this is the energy change, how would I approach this?
To write the equation representing the third ionization energy for chromium (Cr), you are correct in saying that the equation is:
Cr^2+(g) -> Cr^3+ + e^-
This equation represents the process of removing the third electron from a chromium atom, resulting in a chromium ion with a charge of +3.
Regarding the second part of your question, to write the equation for which the given energy change represents the electron affinity of potassium (K), you can follow these steps:
1. First, understand that the electron affinity represents the energy change when an atom gains one electron to form a negative ion.
2. Since the electron affinity of potassium (K) is given as 48 kJ/mol, this energy change will be in the form of an exothermic reaction (energy is released).
3. To write the equation, start with the neutral potassium atom (K) and show the gain of one electron (e^-).
The equation representing the electron affinity of potassium would be:
K(g) + e^- -> K^-(g)
In this equation, the neutral potassium atom (K) gains one electron (e^-) to form the potassium ion (K^-) with a charge of -1. The energy change for this process is 48 kJ/mol, indicating an exothermic reaction.