# NOTE ON pH AND pOH CALCULATION

• The *pH or pOH of a solution* is defined as the degree of acidity or alkalinity of a given chemical solution.
This means that a chemical solution maybe either acidic in character or alkaline(basic) or in between acidicity or alkalinity(neutral).       If you wish to check whether a chemical solution is acidic or basic, you use the instrument known as the *pH metre*         NOTE THIS...     The pH values range from *0 to 14*         This means that if you solve a problem under pH calculation and your answer as pH gives you a negative number or a number greater that 14, then your answer is likely to be wrong.       The lowest answer you should get in pH calculations is zero (0) while the highest is 14.     👇🏼👇🏼👇🏼👇🏼 *Mathematically, the pH of a solution is calculated using the formula*..👇🏼       pH = – log[H^+]     Where [H^+] is the hydrogen ion concentration of the solution given to you or you call it the molarity if the solution.     Note that this is log to base 10.   *You need to know this*...👇🏼       from the knowledge of mathematics, we can rearrange the pH formula as follows👇🏼 Since👇🏼👇🏼   pH = – log [H^+]   This👆🏽is the same as 👇🏼     pH = –1 x log [H^+]   Remember the rule of logarithm which allows us to carry the –1 to the front as the power like this👇🏼     pH = log [H^+]^–¹   Also, according to the law of indices, any number raised to the power if –1 is the same as the inverse of that number (Ex. Y^–¹ = 1/Y)     Therefore,👇🏼   *pH = log 1/[H^+]* ✅     Note this👇🏼👇🏼👇🏼   pH = – log [H^+]   While   pOH = – log [OH^–]     For acids, we work with pH formula, but for bases, we work with pOH formula 