How many d electrons are there in MnO4-? please explain.
To determine the number of d electrons in MnO4-, we need to know the electron configuration of the manganese (Mn) ion.
The MnO4- ion has a charge of -1, meaning it has gained an extra electron. Now, let's break down the steps to determine the electron configuration and determine the number of d electrons:
Step 1: Find the atomic number of manganese (Mn).
The atomic number of manganese is 25. This means it has 25 electrons.
Step 2: Determine the electron configuration of the neutral Mn atom.
The electron configuration of an atom identifies the arrangement of electrons in different energy levels. Mn, being atomic number 25, follows the electron configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d5.
Step 3: Account for the gained electron in MnO4-.
The MnO4- ion has a charge of -1, meaning it gained one extra electron. Since it acquired one electron, we add this electron to the electron configuration of the neutral Mn atom.
In this case, since the additional electron is added to the 4th energy level (designated as n=4), it will be added to the 4s orbital before going to the 3d orbitals. Therefore, the electron configuration of MnO4- is 1s2 2s2 2p6 3s2 3p6 3d5 4s1.
Step 4: Calculate the number of d electrons.
To calculate the number of d electrons, we count the electrons in the 3d orbitals. In the electron configuration of MnO4-, there are 5 electrons in the 3d orbitals. Therefore, MnO4- has 5 d electrons.
In summary, there are 5 d electrons in MnO4-.
To determine the number of d electrons in the MnO4- ion, we need to first understand the electronic configuration of the manganese (Mn) atom in its neutral state.
The atomic number of manganese is 25, which means it has 25 electrons in total. The electronic configuration of a neutral Mn atom can be written as:
1s2 2s2 2p6 3s2 3p6 4s2 3d5
Here, the superscripts indicate the number of electrons in each corresponding orbital. After filling up all the lower energy orbitals, we are left with 5 electrons in the 3d orbital.
Now, let's consider the MnO4- ion. The negative charge of the ion indicates the addition of one extra electron. Therefore, in the MnO4- ion, the Mn atom gains one additional electron and its electronic configuration becomes:
1s2 2s2 2p6 3s2 3p6 4s2 3d5 4p6 5s2 4d5
Since the 4d subshell is located higher in energy than the 3d subshell, d electrons are considered as the valence electrons in this case. Therefore, there are a total of 5 d electrons in the MnO4- ion.