Question

The flask contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains 0.180 M NaOH. It requires 16.0 mL of the NaOH solution to reach the end point of the titration. A buret filled with a titrant is held above a graduated cylinder containing an analyte solution. What is the initial concentration of HCl

Answer 1

The initial concentration of HCl is 0.288 M.

Step-by-step explanation:

To find the initial concentration of HCl, first, we need to determine the number of moles of NaOH used in the titration:

moles of NaOH = concentration of NaOH * volume of NaOH used (in L)

moles of NaOH = 0.180 M * 0.0160 L = 0.00288 mol

Since the balanced equation is 1:1 between NaOH and HCl, the number of moles of HCl in 10.0 mL of the acid solution is also 0.00288 mol.

The initial concentration of HCl can be calculated as:

concentration of HCl = moles of HCl / volume of HCl (in L)

concentration of HCl = 0.00288 mol / 0.0100 L = 0.288 M