Do now: Copy the aim of today’s experiment Aim: to explain how a candle wick works Paraire, 27 Whiringa-ā-rangi 2015

Copy and complete: We tried lighting a small piece of solid wax in a crucible using a lighted splint. The wax... (write down your observations)

Copy and complete: We then tried lighting a small piece of liquid (melted) wax. The wax... (write down your observations) DANGER: DO NOT START UNTIL WE HAVE DISCUSSED SAFETY

1) Place the crucible on a tripod and gauze mat 2) Melt the wax over a very low yellow Bunsen flame. 3) Turn off the Bunsen flame and lift the crucible onto the heat-proof tiles using tongs. 4) Be careful not to spill the hot wax. 5) Try lighting the melted wax using a lighted splint. Keep the crucible on the tripod, Use a blue flame but use it like a blow torch under the crucible, moving it from side to side to generate gentle heating – do a quick demo of the technique.

Using tongs, place a small piece of string, about 3 cm long, into the melted wax. Once some wax has absorbed into the string, try lighting the string. Write down what you observe.

Conclusion: what have we learnt? Solid wax does / does not burn easily. Liquid wax does / does not burn easily. When you light a candle, you _______ the wax around the wick. The wick _______ the liquid wax and pulls it upward. The heat of the flame _______ the wax, and it is the wax _______ that burns. Word list: vapor, absorbs, vaporizes, melt

Use a paper collar to hold a test tube horizontally. Heat some sawdust and when a vapour is produced, test whether the vapour will burn. Record what you observe. Use the fire triangle to explain what you observe. sawdust