Question

007) A (2).29-0.07)-(0.0-V. Question 2. What is the Molarity of a 37.00+0.04% solution of HCI with a Density of 1.178+0.004. Answer with the correct absolute uncertainty Whet ia the 00. .10

Answer 1

Molarity of a solution is the number of moles of solute present per Liter of the solution

i.e Molarity (M) = moles of solute/ volume of solution in L

Now given the HCl is present in the solution as 37.00 ± 0.04 %

That means if we take 100 ml of solution, then volume of HCl in it = 37.00 ± 0.04 ml

Again given density of solution = 1.178 ± 0.004 g/ml

Then mass of HCl present = density * volume

= 1.178 ± 0.004 g/ml * 37.00 ± 0.04 ml

= 43.6 ± 0.16 g

Again we know the molar mass of HCl = 36.5 g/mole

Thus moles of HCl present in solution = mass/ molar mass

= 43.6 ± 0.16 g / 36.5 g/mole

=  1.195 ± 0.0044 moles

Now we know

Molarity (M) = moles of solute/ volume of solution in L

= 1.195 ± 0.0044 moles / 100 ml

= 1.195 ± 0.0044 moles / 0.1 L

= 11.95 ± 0.044 M