Melting Point Flashcards
It refers to the temperature at which the solid and liquid co-exist in equilibrium.
Melting Point
TRUE OR FALSE:
Melting Point is equal to the freezing point of a solid.
TRUE
TRUE OR FALSE:
Melting Point is a physical property used to identify substances and check the purity of solid organic compounds.
TRUE
It occurs when the energy supplied by heating is just sufficient to overcome these forces so that the molecules become mobile.
Melting
For pure substances, MP occurs at ________ and usually quite sharp
very narrow range
What are the important apparatus for Melting Point?
- Fisher-Johns
- Kofler
- Thiele Tube
What are the possible compounds for the determination of the unnknown sample?
- Benzoic Acid
- Naphthalene
- Salicylic Acid
- Urea
- Vanillin
- Fumaric Acid
For the first step in procedure, pulverize the unknown sample with a ________________ and ____________
Watch glass and glass rod
The solid sample must be packed inside a ___________
closed end capillary tube
TRUE OR FALSE
To load the sample in the melting point tube, gently press the open end of the capillary tube into the solid sample.
Repeat this step until the amount of solid pressed into the tube is at most 0.5 cm high.
TRUE
How many trials should we prepare for this experiment?
2
TRUE OR FALSE:
To transfer the solid sample from the open end to the close end of the capillary tube, drop the capillary tube (closed end first) in a long glass tubing
TRUE
Half fill a ________ with mineral oil.
50 mL beaker
Get a thermometer and insert it to a hole in a ___________
cork stopper
**TRUE OR FALSE: **
Determine the melting point range of your sample by recording the initial temperature at which the first signs of melting can be seen and the final temperature at which all the crystals are liquefied.
True
