Calculating Hydrogen Ion Concentration & PH: A Guide by Yonderboy98

[Yonderboy98]

I know what the formal definition of ph is, and I am comfortable with logarithms, anti-logs, and the laws of exponents. Still, I get confused doing actual calculations and would greatly appreciate your input on the following:
Suppose something has a ph of 3.5-How do you calculate the hydrogen ion concentration?
Suppose something has a ph of 7.2- How do you calculate the hysdrogen ion concentration?
Suppose that something has a hydrogen ion concentration of 2.8 times ten to the minus 15-How do you calculate its ph?
Suppose that something has a hydrogen ion concentration of 3.6 times ten to the minus 9-How do you calculate its ph? Yonderboy98

 

[Borek]

[H⁺] = 10^-pH
pH = -log([H⁺])

That's all.

 

[Blueshift5]

's guide provides a helpful overview of calculating hydrogen ion concentration and pH. To answer your questions, we can use the following equations:

1) To calculate the hydrogen ion concentration from pH, we use the formula [H+] = 10^(-pH). In this case, for a pH of 3.5, the hydrogen ion concentration would be 10^(-3.5) = 3.16 x 10^(-4) moles per liter (mol/L).

2) For a pH of 7.2, the hydrogen ion concentration would be 10^(-7.2) = 6.31 x 10^(-8) mol/L.

3) To calculate pH from hydrogen ion concentration, we use the formula pH = -log[H+]. In this case, for a hydrogen ion concentration of 2.8 x 10^(-15) mol/L, the pH would be -log(2.8 x 10^(-15)) = 14.55.

4) Similarly, for a hydrogen ion concentration of 3.6 x 10^(-9) mol/L, the pH would be -log(3.6 x 10^(-9)) = 8.44.

It's important to note that pH is a logarithmic scale, meaning that each unit change in pH represents a 10-fold change in hydrogen ion concentration. This is why a lower pH indicates a higher concentration of hydrogen ions and a higher acidity. I hope this helps with your calculations!