A 70.0 mL portion of a 1.70 M solution is diluted to a total volume of 258 mL. A 129 mL portion of that solution is diluted by adding 119 mL of water. What is the final concentration?

Question

A 70.0 mL portion of a 1.70 M solution is diluted to a total volume of 258 mL. A 129 mL portion of that solution is diluted by adding 119 mL of water. What is the final concentration? Assume the volumes are additive.

Answer 1

So Joana S.,

You ratio the concentration through the dilutions: Final_conc = Initial_conc*(initial_vol/final_vol). Do that for each step successively. Then go back and assess #significant figures; carry that in the final answer.

--Cheers, --Mr. d.