Which ion has larger radius O2- or F 1-?why?
DrBob222, you're still helping people almost 8 years later. Thank you :)
F^- is smaller because the nuclear charge is nigher (by 9 vs 8) and the larger + charge is attracting the electrons that are in the same orbit as oxygen; therefore the outside shell is pulled a little stronger.
Yes, both have 10 electrons.
O has 8 protons pulling on those 10 electrons but F has 9 protons pulling on ten electrons. The 9+ charges will pull those 10 electrons in a little more than the 8 protons will; therefore, F^- will be smaller.
To determine which ion has a larger radius between O2- and F1-, we need to consider their electronic configurations and the concept of effective nuclear charge.
First, let's compare their electronic configurations:
- Oxygen (O) has the atomic number 8, meaning it has 8 protons and 8 electrons. When it gains 2 electrons to become O2-, its electronic configuration becomes 1s² 2s² 2p⁶.
- Fluorine (F) has the atomic number 9, meaning it has 9 protons and 9 electrons. When it gains 1 electron to become F1-, its electronic configuration becomes 1s² 2s² 2p⁶.
Now, let's understand the concept of effective nuclear charge: The effective nuclear charge is the net positive charge experienced by an electron in an atom or ion. It takes into account the attractive force between the negatively charged electrons and the positively charged protons in the nucleus.
The effective nuclear charge experienced by an electron depends on two factors: the number of protons in the nucleus and the number of inner shell electrons shielding the outer electrons from the full positive charge.
Comparing O2- and F1-, both ions have the same electronic configuration in their outermost shell (2p⁶). However, oxygen, being in the second period of the periodic table, has two filled inner shells (1s² and 2s²), while fluorine only has one filled inner shell (1s²).
Since oxygen has more inner shell electrons shielding the outermost electrons from the full positive charge of the nucleus, it has a higher effective nuclear charge compared to fluorine. The higher effective nuclear charge in oxygen causes the outermost electron cloud to be pulled in more strongly, resulting in a smaller ionic radius.
Therefore, O2- has a smaller ionic radius compared to F1-.
don't they both have 10 electrons.
does that mean they both have same radius