How do I go about preparing 50% ethanol and 70% ethanol from 95% ethanol?
To prepare solutions of different concentrations from a given concentration of ethanol, you need to understand the concept of dilution. Dilution involves adding a solvent, usually water, to the solution of the higher ethanol concentration to achieve the desired lower concentration.
Here's how you can prepare 50% ethanol and 70% ethanol solutions from 95% ethanol:
1. Preparation of 50% ethanol solution:
a. Calculate the amount of 95% ethanol and water required to make the desired 50% ethanol solution.
Let's assume you want to prepare 1 liter of the solution:
- Ethanol volume needed = 1 liter * (50% / 95%)
- Water volume needed = 1 liter - ethanol volume needed
b. Take a container, add the calculated volume of 95% ethanol, and then add the calculated volume of water to the container.
c. Mix the solution thoroughly using a stirring rod or by gently swirling the container. Ensure the ethanol and water are fully mixed.
d. You now have a 50% ethanol solution.
2. Preparation of 70% ethanol solution:
a. Follow a similar calculation as done for the 50% ethanol solution to determine the amount of 95% ethanol and water needed for the 70% ethanol solution.
Assuming you want to prepare 1 liter of the solution:
- Ethanol volume needed = 1 liter * (70% / 95%)
- Water volume needed = 1 liter - ethanol volume needed
b. Take a clean container, add the calculated volume of 95% ethanol, and then add the calculated volume of water.
c. Thoroughly mix the solution by stirring or gently swirling until the ethanol and water are well combined.
d. You now have a 70% ethanol solution.
Remember to take necessary safety precautions while handling ethanol, as it is flammable and volatile. Use appropriate protective equipment and work in a well-ventilated area.