The answer is definitely NO!
Logarithms is used everywhere around us. It is so common that we don't even know it exist in our lives! Another example of applying logarithms is in Chemistry. Remember those strips of paper you use in the Chemistry Laboratory to test for acidity and alkali? It makes use of the pH level right? Guess what? The pH Scale also makes use of Logarithms!
How the pH Scale works is almost the same as the Richter Scale. The pH Scale ranges from 0 to 14 when pH level of 7 is neutral. pH less than 7 is acidic and increases it's acidity as it goes down the scale. A pH greater than 7 is alkali and it increases alkali when it goes up the scale. As mentioned just now, the pH scale is logarithmic. How much more acidic is pH 4 to pH 3? How much more alkali is pH 11 to pH 12? It applies the same concept as the Richter Scale -- Magnitude. For every unit, the acidity/alkali increases/decreases by factors of 10. For example, pH 4 is 10 times more acidic than pH 5. pH 3 is 100 times more acidic than pH 5. This is very similar to the magnitude of the earthquake.
So what is the magic formula for pH Scale? Here it is!
http://www.okc.cc.ok.us/maustin/Eval_Logs/Image827.gif
is the hydronium ion concentration in moles per litre. Here's an example: (We are going to calculate the pH of milk)
(pH Formula)
(Substitution)pH = - (-6.4)
pH = 6.4
And thus the pH of milk is about 6.4.
We follow the hydroxide ions by this chart
| [H3O+] | pH | [OH-] | Example |
| 1 X 100 | 0 | 1 X 10-14 | HCl (4%) |
| 1 X 10-1 | 1 | 1 X 10-13 | Stomach acid |
| 1 X 10-2 | 2 | 1 X 10-12 | Lemon juice |
| 1 X 10-3 | 3 | 1 X 10-11 | Vinegar |
| 1 X 10-4 | 4 | 1 X 10-10 | Soda |
| 1 X 10-5 | 5 | 1 X 10-9 | Rainwater (unpolluted) |
| 1 X 10-6 | 6 | 1 X 10-8 | Milk |
| 1 X 10-7 | 7 | 1 X 10-7 | Pure water |
| 1 X 10-8 | 8 | 1 X 10-6 | Egg whites |
| 1 X 10-9 | 9 | 1 X 10-5 | Baking Soda |
| 1 X 10-10 | 10 | 1 X 10-4 | Ammonia |
| 1 X 10-11 | 11 | 1 X 10-3 | |
| 1 X 10-12 | 12 | 1 X 10-2 | Drano® |
| 1 X 10-13 | 13 | 1 X 10-1 | NaOH (4%) |
| 1 X 10-14 | 14 | 1 X 100 |
Isn't Logarithms interesting!?
It is easy to understand too! The same goes for decibels too!
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