Achemist places 2.5316 g of na 2so 4 in a 100 ml volumetric flask and adds water to the mark. she then pipets 15 ml of the resulting solution into a 50 ml volumetric flask and adds water to the mark and mixes to make a solution. she then pipets 15 ml of this new solution into a 50 ml volumetric flask and dilutes to the mark. determine the molar concentration of sodium sulfate in the most dilute solution prepared.

The concentration of the most dilute solution is 0.016M.

Explanation:

First, a solution is prepared and then it undergoes two subsequent dilutions. Let us calculate initial concentration:

First dilution

We can use the dilution rule:

C₁ x V₁ = C₂ x V₂

where

Ci are the concentrations

Vi are the volumes

1 and 2 refer to initial and final state, respectively.

In the first dilution,

C₁ = 0.178 M

V₁ = 15 mL

C₂ = unknown

V₂ = 50 mL

Then,

Second dilution

C₁ = 0.053 M

V₁ = 15 mL

C₂ = unknown

V₂ = 50 mL

Then,

the answer for sodium is 0.186

the answer for rubidium is 0.251