When two atoms of Florine combines, they share an electron pair to complete it's octet. This result is formation of single bond between two fluorine atoms. This process is exothermic in nature, and hence, heat is liberated during the process of bond formation. <span />
Answer: pH of an 
solution is 4.34
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)
Putting in the values:
![pH=-\log[4.58\times 10^{-5}]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5B4.58%5Ctimes%2010%5E%7B-5%7D%5D)
Thus pH of an solution if the ![[H^+]](https://tex.z-dn.net/?f=%5BH%5E%2B%5D)
is ![4.58\times 10^{-5}]](https://tex.z-dn.net/?f=4.58%5Ctimes%2010%5E%7B-5%7D%5D)
is 4.34
Different elements produce different colors of light when heated because the electrons in these elements have different permissible energy levels. When an element is heated, the electrons inside it become excited and move to an higher energy level from the ground state. When the electrons drop from this higher energy level, they typically emit energy quantum, the color of the light that is observed at this stage depends on difference that exist in the two energy levels.<span />
