If 1.72 grams of KHP are needed to exactly neutralize 20.9 mL of a barium hydroxide solution, what is the concentration of the base solution ?
duplicate post.
To find the concentration of the barium hydroxide (base) solution, we can use the concept of stoichiometry and the equation for the reaction between KHP (potassium hydrogen phthalate) and barium hydroxide. The balanced equation for the reaction is:
2KHP + Ba(OH)2 -> 2KOH + Ba(H2P2O8)
From the equation, we can see that two moles of KHP react with one mole of barium hydroxide. The molar mass of KHP is 204.23 g/mol. Therefore, 1 mole of KHP weighs 204.23 grams.
To find the number of moles of KHP used, we divide the mass (1.72 grams) by the molar mass (204.23 g/mol):
Number of moles of KHP = 1.72 g / 204.23 g/mol ≈ 0.00842 mol
Since the stoichiometry ratio is 2:1, the number of moles of barium hydroxide used is half of the moles of KHP:
Number of moles of barium hydroxide = 0.00842 mol / 2 ≈ 0.00421 mol
Now, we know that the volume of the barium hydroxide solution used is 20.9 mL. To find the concentration of the base solution, we need to convert the volume from milliliters to liters:
Volume of barium hydroxide solution (in liters) = 20.9 mL / 1000 mL/L = 0.0209 L
Finally, we can calculate the concentration (molarity) of the barium hydroxide solution by dividing the number of moles of barium hydroxide by the volume:
Concentration of base solution = Number of moles of barium hydroxide / Volume of barium hydroxide solution
Concentration of base solution = 0.00421 mol / 0.0209 L ≈ 0.202 M
Therefore, the concentration of the barium hydroxide solution is approximately 0.202 M.