Bunsen Burners A Tutorial 1 Bunsen Burner A

Bunsen Burners A Tutorial 1

Bunsen Burner A bunsen burner is used for heating samples. l The fuel is natural gas. l 2

Parts of a Bunsen Burner l The parts of the burner include: – gas inlet – burner tube (adjustable) – air control vent – gas control valve 3

Lighting a Bunsen Burner l To light the burner, – step 1: turn on the gas – step 2: open the gas control valve 1/4 to 1/2 turn – step 3: hold the striker at a 45 o angle and ignite the flame 4

Parts of the Flame 5

Adjusting the Flame l Air adds Oxygen which is necessary for combustion l To make the flame burn hotter and larger, open the air mixture valve accordingly l To make the flame burn cooler and smaller, close the air mixture valve accordingly l Opening the gas valve will add more fuel to the mixture but not more Oxygen, and cause incomplete combustion 6

Color Indicators l Different flame types of a Bunsen depend on oxygen supply. burner l What does the flame on the left tell you? – A rich fuel mixture with no premixed oxygen, incomplete combustion produces a yellow sooty flame. l What does the flame on the right tell you? – A fuel and oxygen mixture allows for complete combustion and a hot, blue flame. 7

Color Indicates Temperature l Yellow flame (also called a safety flame) at around 1, 000°C. l Increasing oxygen supply creates a blue appearance l The coolest part of a flame will be red, then progress to orange, yellow, and white as the temperature increases 8