Answer:
Explanation:
To solve this problem, we'll use the formula:
moles of KHP = moles of NaOH
The number of moles of NaOH can be calculated using the formula:
moles = concentration × volume (in liters)
Given that the concentration of NaOH solution is 0.2987 M and the volume used is 20.02 mL (which is 0.02002 L), we can calculate the number of moles of NaOH:
moles of NaOH = 0.2987 M × 0.02002 L
moles of NaOH = 0.005978 mol
Since the reaction between KHP (potassium hydrogen phthalate) and NaOH is 1:1, the number of moles of KHP is also 0.005978 mol.
Now, we can use the formula for calculating moles to find the mass of KHP:
moles of KHP = mass of KHP / molar mass of KHP
Rearranging the formula to solve for the mass of KHP:
mass of KHP = moles of KHP × molar mass of KHP
mass of KHP = 0.005978 mol × 204.2 g/mol
mass of KHP = 1.2221 g
So, the original mass of KHP in the Erlenmeyer flask is approximately 1.2221 g.
