Answer to Question #105272 in General Chemistry for charles sy

Question

A 55.0 mL sample of 1.75 M NaCl and a 45.0 mL sample of 1.00 M NaCl are mixed. Then, additional distilled water is added until the total volume is 500.0 mL. Calculate the molarity of the NaCl in the final solution.

Answer 1

V₁=55 mL=5.5*10^-2 L;

C₁=1.75 M;

V₂=45 mL=4.5*10^-2 L;

C₂=1.00 M;

V₃=500mL=0.5L;

C₃ - ?

n_total(NaCl)=C₁*V₁+C₂*V₂=1.75*5.5*10^-2 + 1*4.5*10^-2 = 0.14125 mole;

C₃=n_total(NaCl) / V₃ = 0.14125/0.5 = 0.2825 M ;

Answer: The molarity of the NaCl in the final solution is 0.2825 M