Convection of Liquids Tube
Publication No. 11936
Convection occurs all around us in our everyday lives, from the air surrounding us to the contents of the food we cook on the stove. Use this demonstration to demonstrate to students the transfer of energy through convection of a liquid.
Food dye, blue
Convection of liquids tube
Wear chemical splash goggles whenever chemicals, heat or glassware is used. Wash hands thoroughly with soap and water before leaving the laboratory. Please follow all laboratory safety guidelines.
Please consult your current Flinn Scientific Catalog/Reference Manual for general guidelines and specific procedures, and review all federal, state and local regulations that may apply, before proceeding. The solution of water and food dye may be rinsed down the drain according to Flinn Suggested Disposal Method #26b.
Student Worksheet PDF
Correlation to Next Generation Science Standards (NGSS)†
Science & Engineering PracticesDeveloping and using models
Constructing explanations and designing solutions
Disciplinary Core IdeasMS-PS1.A: Structure and Properties of Matter
MS-PS3.A: Definitions of Energy
MS-PS3.B: Conservation of Energy and Energy Transfer
MS-ESS2.C: The Roles of Water in Earth’s Surface Processes
HS-PS3.A: Definitions of Energy
HS-PS3.B: Conservation of Energy and Energy Transfer
HS-ESS2.B: Plate Tectonics and Large-Scale System Interactions
Systems and system models
Energy and matter
Stability and change
MS-PS4-2: Develop and use a model to describe that waves are reflected, absorbed, or transmitted through various materials.
Answers to Questions
Heat energy can be transferred by three methods—conduction, convection and radiation. Conduction is the transfer of heat through direct contact. Radiation occurs when energy is transferred by electromagnetic waves, such as the sun heating the Earth. Convection is the transfer of thermal energy by the movement of molecules from one part of a fluid (gas or liquid) to another.
This same phenomenon occurs in nature in air and water. It occurs when a cool more-dense fluid displaces a warmer less-dense fluid. For example, during the day the water of the lake is cooler than the land. During the day the sun heats the air above the nearby land causing the molecules to move faster and become less dense. Cool air off of the lake flows towards the land, displaces the warm air and creates a cool breeze. As this new cool air is heated from the warmth of the ground, it rises and the cycle repeats.
Introduction to Physical Science. Glencoe McGraw Hill: New York; 2002; pp 292–293. Science Spectrum, Physical Science: Holt, Rinehart and Winston: Orlando; 2008; pp 480–481.