how to get a 70% ethanol?

Assume that the starting ethanol is 100%

Total volume = 3000µL

Concentration = 2100/3000*100 = 70%

Answer: YES

Well, it depends on the molarity of the ethanol solution that you start out with. We use the dilution equation. Assume I want to finally obtain 50 mL solution of 70% ethanol, starting with 95% ethanol.

:: Dilution equation: (molarity initial)(initial volume) = (molarity final)(final volume)

To find the initial volume divide molarity initial from the equation:

initial volume = (final molarity)(final volume) / (initial molarity) = (0.70 M)(50 mL) / (0.95 M)

Initial volume = 36.84 mL of ethanol.

amount of water required to reach 50 mL solution = 50 mL - 36.85 mL = 13.16 mL of water that must be added to the 36.84 mL of 0.95 M ethanol to obtain a 50 mL diluted solution of 70% ethanol.