Winnowing
This method is used to separate a solid-solid mixture by using the wind or fast moving air. The mixture is made up of light weight solid and a heavier one. Example; maize and chaff or saw dust and nails.
How to perform winnowing
• Gather a maize containing chaff in a basin.
• Throw the mixture into the air when the wind is blowing.
• Continue the process till the chaff is blown away.
Observation
The wind blew the chaff away whilst the maize fell back into the basin.