OVERVIEW
70% Ethanol is used as a disinfectant in labs. It is also used for washing DNA pellet to remove excess salt. It can be prepared by diluting 95% ethanol. For the preparation of 70% ethanol for analytical work, use analytical grade ethanol.
To prepare 1L of 70% Ethanol, take 736.84 ml of 95% ethanol and make up the final volume to 1L with water.
REQUIREMENTS
Reagents and solutions
95% Ethanol
Deionized water
Equipment and disposables
Measuring cylinder
COMPOSITION
70% aqueous solution of ethanol
OBJECTIVE
Preparation of 1L of 70% ethanol in water
PREPARATION:
Use personal protective equipment (lab coat, gloves, goggles, etc) for your safety and follow your institute’s guidelines.
Step 1: Take 736.84 ml of 95% ethanol in a measuring cylinder.
Step 2: Adjust the final volume to 1000 ml with water. Mix it.
Note: You need to add 263.16 ml water.
STORAGE
Solution can be stored at room temperature.
| Follow the table to prepare 70% Ethanol of different volumes. | ||||
| Ingredients / Volume | 500 ml | 1000 ml | 2500 ml | 10000 ml |
| 95% Ethanol | 368.42 ml | 736.84 ml | 1842.11 ml | 7368.42 ml |
Water | 131.58 ml | 263.16 ml | 657.89 ml | 2631.58 ml |
