pH
pH
What is it?
"pH" is an scale . It looks something like this:
Red 1.0
Pink 2.0
Orange 3.0
Beige 4.0
Yellow 5.0
Lime Green 6.0
Green 7.0
Dark Green 8.0
Turquoise 9.0
Pale Blue 10.0
Blue 11.0
Dark Blue 12.0
Violet 13.0
Purple 14.0
In Chemistry it is important to know how acidic or basic an Aqueous Solution is.For this Søren Peder Lauritz Sørensen a Danish chemist discover it in 1909 at Carlsberg Laboratory to accommodate definitions and measurement in terms of electrochemical cells it was revised to the modern pH in 1924.
Meaning
In first paper of pH it was written something like this "pH" "p" was lowercase and "H" as subscript of "p". In pH the exact meaning of the "p" in "pH" is disputed, but according to the Carlsberg Foundation, pH stands for "power of hydrogen".It has also been suggested that the "p" stands for the German Potenz. As the Carlsberg Laboratory was French-speaking others refer to French puissance.Another suggestion is that the "p" stands for the Latin terms pondus hydrogenii, potentia hydrogenii or potential hydrogen. It is also suggested that Sørensen used the letters "p" and "q" (as they are commonly paired letters in mathematics)simply to label the test solution (p) and the reference solution (q). Currently in chemistry, the p stands for "decimal cologarithm of", and is also used in the term pKa, used for acid dissociation constants.
Calculation
The pH scale is a logarithmic scale. The pH approximates the negative of the base 10 logarithm of the molar concentration of hydrogen ions in a Aqueous Solution. The equation is this:
Mathematically the pH value of a solution can be negative or positive but in real life it is considered from 0 to 14. Here from 0 to 6 the values are acidic, 7 is neutral and from 8 to 14 the values are basic. Here the highest value of acidity is 0 and it decreases gradually to 6 and the highest value of basicity is 14 and it decreases gradually to 8.
Examples
For example, for an Aqueous Solution with a hydrogen ion activity of 4×107 we get 1/(4×107) = 25×10-9, thus such the solution has a pH of log10(25×10-9) = -7.602
Importance and uses
Thought for example you are a chemist and you have made an antiseptic solution. Then you have use it and saw that it causes skin problems. Then you again made it with a high or low acidity or basicity but you don't know how acidic or basic it is. So you aren't sure that weather it's harmful or not. So in order to be sure about this fact you have to know how much acidic or basic it is. You also have to know weather your skin is familiar with this or not. So you also have to know the value of acidity or basicity that your skin support. And pH also told you the same things. So if you know the pH of your antiseptic solution then you can compare it with the pH value of humans skin. And if it's familiar with humans skin then you can use it otherwise it can be very dangerous. Again if you want to plant a tree you must have to know the pH of the soul where you want to plant the tree if the pH is very acidic then the tree will die. Again while using various chemical product to know the pH is very important because if you touched any high acidic product without any hand globes it can do many dangerous things with your hand. So now you can consider that how important pH is
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