Purpose: Find crystallization temperatures for 7 concentrations of KNO3 and make a solubility graph

Materials: KNO3, test tube, stir rod, weigh boats, hot plates, thermometer, 10 mL graduated cylinder.

Procedure:

-In two test tubes, put exactly 5 mL water in each

-Put assigned amount KNO3 in each

-Heat in hot water bath until dissolved- you may stir with sitr rod

-Find crystallization temperature as test tube cools -use a cold water bath for lower concentrations

Table:

Grams KNO3 Grams H2O Grams KNO3 per 100g H2O Actual Crystallization Temp. Class Average
2 5 40 24 25, 24, 24 24, 26, 23, 24
3 5 60 38 41, 40, 33, 46 42, 37, 38, 40
4 5 80 49 55, 50, 55 49, 51, 50, 53
5 5 100 57 57, 66, 64 59, 57, 62, 62
6 5 120 66 71, 71, 64 66, 66, 64, 72
7 5 140 73 77, 70, 71 73, 77, 72, 73
8 5 160 78 79, 77, 80 81, 80, 75, 79

solubility-of-kno3-graph

Leave a Reply

Be the First to Comment!

avatar
wpDiscuz