An aqueous solution has a hydronium ion concentration of #6 * 10^-9# mole per liter at 25°C. What is its pH?

2 Answers
May 9, 2016

#pH=8#

Explanation:

The pH of a solution could be calculated using the concentration of hydronium #H_3O^+# by: #pH=-log[H_3O^+]#

Therefore, #pH=-log(6xx10^(-9))=8.22 =8 ("1 significant figures")#

Acids & Bases | Nature, Strength & pH Scale.

May 9, 2016

#pH =8.22#

Explanation:

So what is #pH#?

Here it is simply the function #pH=-log_10[H_3O^+]#, #pH# derives from the French #"pouvoir hydrogene"#, #"the power of hydrogen"#.

We have #[H_3O^+]# and we have a calculator, so we press the buttons.

It is worthwhile to review the logarithmic function, and see why the use of logarithms (and slide rules) was absolutely widespread among scientists and engineers in a pre-calculator world.