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Answer:

The melting point of pure naphthalene is 80.5oC.

3.3.0 Melting point of naphthalene with a capillary tube

Explanation:

• Melting point of naphthalene with a capillary tube.
• For a more accurate way of finding the melting point
• Make a capillary tube by drawing out a glass tube over a hot flame.
• Put a very small amount of naphthalene in a capillary tube sealed at one end.
• Attach a thermometer to the capillary tube, a sealed end down.
• Put the thermometer and capillary tube in a container of water and slowly heat the water while stirring with the thermometer and capillary tube.
• Do not let water enter the capillary tube.
• To find the melting range, note the temperature when the naphthalene melts, leave to cool, and note the temperature when the naphthalene solidifies.

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