gcsescience.com                                                                              gcsescience.com

Collecting Gas

How is a Gas Collected Over Water?

A gas that is not soluble (or only slightly soluble) in water
can be collected over water.
Examples of gases that can be collected by this method
are hydrogen and oxygen.

A tube from the flask that is giving off the gas
is placed under water. A test tube full of water is
placed upside down above the end of the tube
to collect the gas as shown in the picture below.

Collecting Gas Over Water

As the gas bubbles into the test tube it displaces the water
until the test tube is
filled with the collected gas.

gcsescience.com     The Periodic Table      Index      Chemistry Quizzes    gcsescience.com

Home      GCSE Chemistry      GCSE Physics

Copyright © 2015 gcsescience.com. All Rights Reserved.