1. Physical vs Chemical Changes: Inquiry Activity

2. Let’s go shopping… Collect the following items in your basket:
Goggles!!
100mL beaker
Stir rod
Sugar cube
Alka seltzer tablet
Piece of zinc
Bottle of hydrochloric acid (HCl)
Watch glass dish
Bottle of calcium chloride
Bottle of sodium carbonate

3. 1a- Solubility in Water What you need:
Small beaker with 100 mL of water
Stir rod
Sugar cube

4. Mix the sugar cube into approx 100 mL of water. Gently stir the mixture.
Observations:
Sugar dissolves into the water
Fully mixes and forms a solution
Explanation:
Sugar is soluble in water
Physical property

5. 1b- Reclaim our starting material!
What you will need:
Your sugar solution
Hotplate (one for the class)

6. Add a small amount of your sugar solution to the class beaker
Add a small amount of your sugar solution to the class beaker. I will boil the solution on the hot plate.
Observations:
Water boils off from the solution
Sugar crystals are left behind
Explanation:
Sugar is reclaimed from the solution
Evidence that this was a physical change!

7. 3- Reactivity with Water
What you will need:
¼ piece Alka seltzer tablet
Small beaker

8. Add ¼ of a tablet into approx. 50 mL of water and observe.
Observations:
Tablet produces bubbles of gas
Slowly dissolves into the water
Explanation:
Chemical reaction
New substance (gas) is given off
Can’t be reversed

9. 4- Reactivity with Acid What you will need: Goggles Watch glass Zinc
Hydrochloric Acid

10. Wear your goggles. Place a small piece of zinc on the watch glass
Wear your goggles! Place a small piece of zinc on the watch glass. Add a few drops of hydrochloric acid.
Observations:
Zinc produces bubbles of gas
A new substance forms
Explanation:
Zinc metal reacts with the acid to form hydrogen gas
Chemical change

11. 5- New Substance forming
What you will need:
Goggles
Watch glass
Calcium chloride
Sodium carbonate

12. Add a few drops of each chemical together in the watch glass.
Observations:
New colour is seen
Small, solid pieces can be seen (called a precipitate)
Explanation:
A new substance is formed
Not a reversible reaction
Chemical change

13. 2- Calculate Density
Select a series of blocks. Determine the volume. Use the digital balance to measure the mass. Calculate the density. Compare with another group.
Observations:
Use this space to record your calculations
Explanation:
Physical property
Density of the different block shapes should be the same!