Calculate pH for strong base solution: 1.100 g of KOH in 550.0 mL of solution
1.1g/molar mass KOH = mol KOH = mols OH^-
M= mols/L, then convert to pOH and to pH.
Well...
You know that KOH is a strong base... So it ionizes completely.
KOH----> K+ +OH-
So you need the molarity of KOH...
So..
1.100g/.5500 L x 1mol/56.11g KOH = 0.0356 M KOH
So since KOH is strong...
Concentration KOH, K+, and OH- = 0.0356M
pOH=-log(0.0356)
pOH= 1.45
pOH+pH=14
pH= 14-1.45
So pH=12.55 Tada!
To calculate the pH of a strong base solution, you need to know the concentration or molarity of the base. In this case, we can determine the molarity of the KOH solution by calculating the number of moles of KOH and dividing it by the volume of the solution.
Step 1: Calculate the number of moles of KOH.
To calculate the number of moles, we will use the formula:
moles = mass / molar mass
The molar mass of KOH is the sum of the atomic masses of potassium (K), oxygen (O), and hydrogen (H):
K = 39.10 g/mol
O = 16.00 g/mol
H = 1.01 g/mol
So, the molar mass of KOH is:
molar mass of KOH = 39.10 + 16.00 + 1.01 = 56.11 g/mol
Now we can calculate the moles of KOH:
moles of KOH = mass of KOH / molar mass of KOH
moles of KOH = 1.100 g / 56.11 g/mol
Step 2: Calculate the molarity of the KOH solution.
The volume of the solution is given as 550.0 mL. To convert it to liters, we divide by 1000:
volume of the solution = 550.0 mL / 1000 = 0.550 L
Molarity (M) is defined as moles of solute per liter of solution:
molarity of KOH solution = moles of KOH / volume of the solution
Now, we can calculate the molarity of the KOH solution:
molarity of KOH solution = moles of KOH / volume of the solution
molarity of KOH solution = (1.100 g / 56.11 g/mol) / 0.550 L
Step 3: Calculate the pOH of the solution.
The pOH is calculated using the equation:
pOH = -log10(MOH)
Since KOH is a strong base, it dissociates completely in solution. So the concentration of hydroxide ions (OH-) is equal to the molarity of the KOH solution:
[OH-] = molarity of KOH solution
Now, calculate the pOH:
pOH = -log10([OH-])
Step 4: Calculate the pH of the solution.
The pH is related to the pOH by the equation:
pH + pOH = 14
Now, calculate the pH:
pH = 14 - pOH
Now that you have the pOH and pH, you can calculate the pH of the strong base solution.