A student makes the following series of dilutions, beginning with a concentrated solution of red dye. Dilution #1: 1 ml concentrated dye + 4 ml water (makes 5 ml total) Dilution #2: 1 ml Dilution #1 + 4 ml water (makes 5 ml total) Dilution #3: 1 ml Dilution #2 + 9 ml water (makes 10 ml total) Dilutions #1 and #2 are both ____-fold dilutions for a combined dilution of ____-fold. Dilution #3 is a ____-fold dilution., so that altogether the red dye has been diluted ____-fold. If the concentrated dye that the student started with was at a concentration of 10-4 M, at the end the concentration will be ____M.
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Step 1: Dilution #1 is a 5-fold dilution, so the concentration after dilution #1 is \( \frac{1}{5} \times 10^{-4} M = 2 \times 10^{-5} M \). Show more…
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