Page 54 - Big Ideas Year 9 sciPAD 2025

PHOTOCOPYING PROHIBITED
© Silverback Academic Media
54 SCIPAD - BIG IDEAS - BOOK 1
THE NATURE OF MIXTURES
1. Identify and describe the process occurring in the:
(a) round bottom flask. 


(b) water jacket. 


2. Describe the difference between the water going into the water jacket and the water
coming out of the water jacket. 

3. Distillation can also be used to separate a mixture of liquids that have different boiling
points. Suggest how the temperature of the round bottom flask must be controlled to
separate the liquids. 


4. Suggest why the apparatus shown above could not separate a solution containing two
liquids with the same boiling point. 


The solution is heated in a
round-bottomed flask.
The liquid gains heat energy and begins
to evaporate. The vapour rises up the
column.
A thermometer allows the careful control of temperature
to ensure that the evaporated solvent is not too hot.
A water jacket cools the
vapour, causing it to condense
back into a liquid.
The vapour has now condensed back into
a liquid and is collected in a beaker or flask.
Warm
water out
Cold
water in
1
2
5
3
4
Distillation
Evaporation is a simple technique for separating a solid dissolved in a liquid. However, what if we
want to collect the solvent? We need to trap the solvent as it evaporates and condense it back
into a liquid. Scientists call this process distillation.
Unchecked Sample Pages
For Review Purposes Only - Photocopying Prohibited
www.scipad.co.nz