All High School Chemistry Resources
Example Questions
Example Question #61 : Acid Base Chemistry
An arterial blood sample from a patient has a pH of 7.4. One day later, the same patient has an arterial blood pH of 7.15. How many times more acidic is the patient's blood on the second day?
The equation to calculate pH is:
The normal pH of arterial blood is around 7.4. This reflects a concentration of hydrogen ions that can be found using the pH equation.
Using similar calculations for the second blood sample, we can find the hydrogen ion concentration again.
Now that we have both concentrations, can find the ratio of the acidity of the two samples.
You may know from biological sciences that this is approaching a lethal level of acidosis.
Example Question #22 : Acids And Bases
You find a bottle in a lab that has a solution of acid. The acid has the following dissociative properties:
What is the pH of this solution?
is a strong acid, meaning it will completely dissociate in solution. As such, the concentration of the acid will be equal to the proton concentration. Thus, to find pH, you should just plug the molar concentration of the acid solution into the pH formula.
Example Question #62 : Acid Base Chemistry
Calculate the pOH and hydroxide ion concentration in an organism whose blood pH was measured to be 8.00 at .
To find the pOH note that . Therefore one can solve for . Plug in the value of the organism's blood pH and solve to get
We find the concentration of hydroxide ions based on the formula for pOH:
.
Example Question #61 : Acids And Bases
Calculate the pH of the following solution at :
Use the the dissociation constant for water to calculate the concentration of hydrogen ions and then convert to the pH scale.
Rearrange the dissociation constant to solve for the hydrogen ion concentration:
Plug in the given concentrations to find the actual hydrogen ion concentration:
Convert the hydrogen ion concentration to pH scale:
Example Question #62 : Acids And Bases
Calculate the of a solution.
Relevant equations:
is a strong acid, so
Combine equations:
Plug in values: