What is the pH of the solution created by combining 12.00 mL of the 0.10 M base with 8.00 mL of the 0.10 M acid
base acid
NaOH HC2H3O2
correction: the base is NaOH and acid is HC2H3O2
I'll let HAc stand for HC2H3O2.
Then NaOH + HAc ==> NaAc + H2O.
Calculate mols NaOH. mols = L x M = ??
Calculate mols HAc. mol = L x M = ??
They react in 1:1 ratio. Use logic to determine how much NaAc is produced and how much NaOH remains unreacted. Note: Check the problem. Problems of this type USUALLY have excess acid, not base, so it makes a buffer solution. This one is not a buffer.
To determine the pH of the solution created by combining a base (NaOH) and an acid (HC2H3O2), we need to calculate the concentration of the resulting solution after mixing.
First, let's calculate the moles of base and acid in the given volumes of their solutions.
Moles of base (NaOH):
moles base = volume base × concentration base
moles base = 12.00 mL × 0.10 mol/L = 1.20 mmol
Moles of acid (HC2H3O2):
moles acid = volume acid × concentration acid
moles acid = 8.00 mL × 0.10 mol/L = 0.80 mmol
Next, we need to determine the limiting reactant. The limiting reactant is the one that is completely consumed and determines the amount of products formed. In this case, it is the reactant that has fewer moles.
Since the moles of acid (0.80 mmol) are less than the moles of base (1.20 mmol), the acid is the limiting reactant.
Now, let's determine the concentration of the solution after the reaction is complete. As the acid (HC2H3O2) will be completely consumed, the final volume of the solution will be the sum of the volumes of the base and acid solutions.
Final volume of the solution = volume base + volume acid
Final volume of the solution = 12.00 mL + 8.00 mL = 20.00 mL
The moles of acid (0.80 mmol) will react with an equal number of moles of base (NaOH). Since the volume is now 20.00 mL, the concentration of the resulting solution will be:
Concentration of the resulting solution = total moles / final volume
Concentration of the resulting solution = (moles base + moles acid) / final volume
Concentration of the resulting solution = (1.20 mmol + 0.80 mmol) / 20.00 mL
Now, we convert the final volume from mL to L:
Final volume in liters = final volume / 1000
Final volume in liters = 20.00 mL / 1000 = 0.020 L
Finally, we can calculate the concentration of the resulting solution:
Concentration of the resulting solution = (1.20 mmol + 0.80 mmol) / 0.020 L
Once we have the concentration of the resulting solution, we can determine its pH by using the pH formula:
pH = -log10(concentration)
Substitute the concentration of the resulting solution into the formula and calculate the pH.