Finding pH of diluted solutions

Predicting the pH of diluted solutions : Predicting the pH of diluted solutions Online Lesson 3.2.4

Dilution : Dilution In the first half of this unit you learnt how to dilute a solution by adding water to the initial solution. Acidic solutions contain H3O+ and dilution reduces the [H3O+] therefore affecting the pH

How does dilution affect pH? : How does dilution affect pH? If the [H3O+] is reduced (by adding water) Then the solution is less acidic Then the pH goes higher (ie moves towards 7).

How to solve pH and dilution questions. : How to solve pH and dilution questions. Find the new concentration of H3O+ after the dilution Use pH = -log[H3O+] to solve for pH

Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water.  : Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water. Calculate the hydronium-ion concentration and the pH of the resulting solution.

Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water.  : Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water. Calculate the hydronium-ion concentration and the pH of the resulting solution. civi = cfvf

Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water.  : Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water. Calculate the hydronium-ion concentration and the pH of the resulting solution. civi = cfvf

Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water.  : Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water. Calculate the hydronium-ion concentration and the pH of the resulting solution. HCl is a strong acid and is monoprotic so the [H3O+] is 0.12 mol/L

Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water.  : Example 1 - 8.0 mL of 0.30-mol/L HCl(aq) is mixed with 12.0 mL of water. Calculate the hydronium-ion concentration and the pH of the resulting solution. HCl is a strong acid and is monoprotic so the [H3O+] is 0.12 mol/L

b. If 1.0 mL of the solution produced in part a. is added to 9.0 mL of pure water, calculate the resulting pH of the new solution. : b. If 1.0 mL of the solution produced in part a. is added to 9.0 mL of pure water, calculate the resulting pH of the new solution.

b. If 1.0 mL of the solution produced in part a. is added to 9.0 mL of pure water, calculate the resulting pH of the new solution. : b. If 1.0 mL of the solution produced in part a. is added to 9.0 mL of pure water, calculate the resulting pH of the new solution.

b. If 1.0 mL of the solution produced in part a. is added to 9.0 mL of pure water, calculate the resulting pH of the new solution. : b. If 1.0 mL of the solution produced in part a. is added to 9.0 mL of pure water, calculate the resulting pH of the new solution.

c. Suppose 1.0 mL of the solution from part b. is added to 9 mL of pure water. Predict the resulting pH without doing any calculations. : c. Suppose 1.0 mL of the solution from part b. is added to 9 mL of pure water. Predict the resulting pH without doing any calculations.

c. Suppose 1.0 mL of the solution from part b. is added to 9 mL of pure water. Predict the resulting pH without doing any calculations. : c. Suppose 1.0 mL of the solution from part b. is added to 9 mL of pure water. Predict the resulting pH without doing any calculations. The pH of this solution will be 2.92. Every time the [H3O+(aq)] decreases by a factor of 10, the pH goes up one full unit since the solution becomes less acidic.

Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. : Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. step 1 - Calculate the hydroxide-ion concentration of the original solution.

Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. : Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. step 1 - Calculate the hydroxide-ion concentration of the original solution.

Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. : Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. Step 2 - Calculate the new hydroxide-ion concentration of the dilute solution.

Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. : Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. Step 2 - Calculate the new hydroxide-ion concentration of the dilute solution.

Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. : Example 2 - 200 mL of a strontium hydroxide solution, Sr(OH)2(aq), with a pOH of 3.92 is diluted by adding 250 mL of water. Determine the pOH of the diluted solution. Step 3 - Calculate the new pOH.

Homework : Homework