The normal boiling point of water is 100ºc and the normal boiling point of ethanol is 78.5ºc. these two liquids are soluble in each other. what technique would you use to separate these two liquids from the solution?

Fractional Distillation

Explanation:

Fractional Distillation is the appropriate technique to separate a mixture of ethanol and water because this technique relies on the difference between the boiling point of liquid substances.

The boiling point of ethanol is 78.5ºC and the boiling point of water is 100ºC, so when these substances are heated, ethanol will evaporate at 78.5ºC and water will remain as a liquid while the temperature doesn't reach the boiling point of water.

The mixture is poured into a round bottle flask and is heated until ethanol's boiling point is reached (78.5ºC). Ethanol turns into a gas and rises through a fractioning column attached to the flask. The vapour lows its temperature along the column and when the temperature at the top of the column reaches 78.5ºC ethanol passes to a condenser.

A condenser is an apparatus attached to the column that causes the condensation of the vapour. Once ethanol passes through the condenser it turns into a liquid which is collected in a beaker.

When all the ethanol is collected, the temperature is raised to the boiling point of water (100ºC) and it is collected in a different beaker.

That way ethanol will be in a flask and water in another flask.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e