Question

A 25.0mL sample of 0.115M RbOH is titrated with 28.75 mL of HCL(solution=HCL+RbOH- H20+RbCL)
A)How many moles of RbOH are required?
B)How many grams of RbOH are required (MM RbOH= 102.468)
C)What is the molarity of the HCL solution?

Answer 1

1) figure out moles of RbOH using the formula

n = cV (n = no. of moles, c = conc. in mol/L and V is volume in L)
2) convert this value of n to mass in grams using the formula n = mass/molar mass

3) Molarity = n(HCl)/V(HCl) So calculate number of moles of HCl needed (hint: really it is the same as the moles of RbOH based on your chemical formula!) Make sure your V is in litres.