Calculate the volume in mL of a stock solution of 100% ethanol, required to prepare 2 L of a 70% solution of ethanol in dH2O

For example, to make 70% ethanol from 95% ethanol, take 70 mL of 95% ethanol and add enough water to bring the volume to 95 mL. You will then have 95 mL of 70% ethanol. This works for any dilution and all that is required is a large enough graduated cylinder.

When using liquid reagents, the percent concentration is based upon volume per volume, i.e. #ml/100ml. Example 2: If one wished to make a 70% ethanol solution, 70 ml of 100% ethanol would be dissolved in 30 ml of water (or the equivalent for whatever volume was needed).

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.