arrange the elements in increasing order of their size F-,Li+ ,Na+ ,Cl-
Answers
Answer:
The order in decreasing size would be Cl- > F- > Na+ > Li+.
This can be explained by the following logic.
Cl- would be the largest because it has the largest number of electrons, i.e. 18. So, the electron- electron repulsion would be maximum in the chloride ion.
Similarly Li+ would be the smallest because it has only 2 electrons and therefore the least electron- electron repulsion.
When comparing F- and Na +, we have to be careful, as both of them have 10 electrons. Experimental results show that F- is slightly larger than Na+(119 pm as compared to 116 pm).
One way of explaining this is that in the case of fluoride ion, there are only 9 protons holding the 10 electrons in orbit whereas the sodium ion has 11 protons holding the same number of electrons. So Na+ is smaller due to the larger attractive force of the protons.