How many moles of H3O+ or OH-
must you add per liter of HA solution to adjust its pH from 9.75 to 9.01? Assume a negligible volume change.
……….x 10………Moles of ……………………..h3O+ or
OH-
I got 4.6001 x 10-5 M of h3o+...but it was wrong
To calculate the moles of H3O+ or OH- required to adjust the pH from 9.75 to 9.01, you can use the equation for pH:
pH = -log[H3O+]
First, convert the pH values to H3O+ concentration:
[H3O+]1 = 10^(-pH1)
[H3O+]2 = 10^(-pH2)
where pH1 = 9.75 and pH2 = 9.01.
[H3O+]1 = 10^(-9.75)
[H3O+]2 = 10^(-9.01)
Now, find the difference in moles of H3O+ between the two concentrations:
δ[H3O+] = [H3O+]2 - [H3O+]1
Next, since H3O+ and OH- are related by water autoionization, the concentrations of OH- can be calculated using the equation:
[H3O+][OH-] = 1.0 x 10^(-14)
Using this equation, you can find the concentration of OH- in terms of the H3O+ concentration:
[OH-] = (1.0 x 10^(-14))/[H3O+]
Finally, multiply the value of OH- concentration by the volume (1 liter) to find the number of moles of OH- required:
moles of OH- = [OH-] x volume
moles of OH- = [OH-] x 1
I hope this helps you to calculate the final answer.
To calculate the number of moles of H3O+ or OH- required to adjust the pH of a solution, you can use the concept of pH and the formula for pH:
pH = -log[H3O+]
First, let's find the concentration of H3O+ in the HA solution at pH 9.75:
pH = -log[H3O+]
9.75 = -log[H3O+]
To isolate [H3O+], you need to raise both sides of the equation to the power of 10:
10^9.75 = [H3O+]
This gives you the concentration of H3O+ in the solution at pH 9.75.
Next, let's calculate the concentration of H3O+ in the HA solution at pH 9.01:
pH = -log[H3O+]
9.01 = -log[H3O+]
Again, raise both sides of the equation to the power of 10:
10^9.01 = [H3O+]
This gives you the concentration of H3O+ in the solution at pH 9.01.
To find the change in concentration of H3O+ from pH 9.75 to pH 9.01, subtract the concentration at pH 9.01 from that at pH 9.75:
Change in concentration = [H3O+] (pH 9.75) - [H3O+] (pH 9.01)
Now you can convert the change in concentration to moles per liter. Remember to assume a negligible volume change:
Change in moles = Change in concentration (in M) * Volume of solution
Given that the volume of the solution is 1 liter, the change in moles will be equal to the change in concentration.
So, the number of moles of H3O+ or OH- required per liter of HA solution to adjust the pH from 9.75 to 9.01 is equal to the change in moles calculated above.