Concept: According to the basic concept of the electronic configuration of the element, the electron can be filled first in those shell which has least energy or (n +l) value. Here, n is the principal quantum number on shell and l is the azimuthal quantum number.
Since, the first shell has least value of energy in any atom. So, it should be filled first.
Hence, the correct statement can be written as;
When diagramming an atom, the electron shells _nearest to _ the nucleus must be filled first.
.0002345 I believe this is correct
Explanation:
Relation between pH and concentration of hydrogen ions is as follows.
pH = ![-log [H^{+}]](https://tex.z-dn.net/?f=-log%20%5BH%5E%7B%2B%7D%5D)
So, it means that an increase in the value of pH will show that there occurs a decrease in concentration of hydrogen ions.
Therefore, the solution becomes basic in nature.
On the other hand, a decrease in the value of pH will show that there occurs an increase in the concentration of hydrogen ions.
Therefore, the solution becomes more acidic in nature.
Hence, if the pH of a solution is decreased from pH 8 to pH 6 it means that the concentration of hydrogen ions has increased in the solution.
BY CHECKING THE REACTIVITY OF AN ELEMENT WHICH IS MOST REACTIVE OR NOT AND YOU STUDY TYPE OF CHEMICAL REACTION IN 1 CH AND YOU CHECK THE REACTIVITY OF ELEMENTS IN 3 CH METALS AND NON METALS PAGE NO 45 IN NCERT BOOK