Types of Solids Lab
Observable properties depend on the type of bonding that holds the molecules, atoms, or ions together in each solid. Depending on the type of bonding, solids may be described as ionic, molecular, or atomic solids. The properties to be studied are relative melting point, solubility in aqueous solution, and electrical conductivity.
Test-tube rack calcium carbonate (CaCO3)
graduated cylinder, 10 mL fructose (C6H12O6)
LED conductivity tester sodium chloride (NaCl)
Deionized water stirring rod
test tubes, small (3)
1. Place a small sample of each substance into a test tube and place it in a test tube rack.
2. Place the beaker containing the calcium carbonate in a beaker and put it on the hot plate.
3. Observe what happens to the solid as it is heated. As soon as the solid melts (if it melts), carefully remove the test tube from the beaker using the test tube tongs and place it back in the test tube rack to cool. The test tube will be VERY hot so do NOT touch it. Do not heat any substance for more than 5 minutes. If nothing happens after 5 minutes, remove the test tube and place it in the test tube rack to cool. There may be some substances that will not melt.
4. Repeat this procedure for the fructose and the sodium chloride.
3. Record which substances melted in your data table.
4. Leave the test tubes in the test tube rack to cool and continue to the next step.
5. Place a small sample of each substance into separate small beakers.
6. Touch the electrodes of the conductivity tester to each solid. After each test, rinse with
deionized water and carefully dry the electrodes. Record which substances conducted electricity.
7. Add 20mL of deionized water to each beaker and stir to try to get the solid to dissolve.
8. Record which substances dissolved in the water.
9. Touch the electrodes of the conductivity tester to each solution. After each test, rinse with
deionized water and carefully dry the electrodes. Record which substances conducted electricity when dissolved in water.
1. Place any solids left in beakers in a paper towel and put in the trash.
2. Place the test tube with the fructose in the broken glass box. DO NOT PUT IN THE TRASH!!!!
3. Rinse, brush, and dry all glass wear and return it to the counter.
DATA TABLECalcium carbonate (CaCO3) / Fructose (C6H12O6) / Sodium Chloride (NaCl)
Melted (“yes” if it did, “no” if it did not)
Solid conductivity (“yes” if it did, “no” if it did not)
Dissolve in water (“yes” if it did, “no” if it did not)
Aqueous (dissolved in water) conductivity (“yes” if it did, “no” if it did not)
1. Identify the type of solid for each substance. (Use your notes)
a. (CaCO3) (hint:CO3 is called a polyatomic ion. It has covalent bonds but has properties of an ion). –
b. (C6H12O6) -
c. (NaCl) –
2. An unknown sample had the following results:
a. did not melt
b. did not conduct electricity as a solid
c. dissolved in water
d. conducted electricity when dissolved
What type of solid is this unknown substance? Explain your answer. (Use your notes)
3. Explain why ionic solids do not conduct electricity, but in solution they become good conductors.
4. Why do you think that we used deionized water for this experiment and not tap water?