1. The Candle Experiment
* Materials: Candle, jar or glass, balance scale
* Procedure:
1. Weigh the candle before burning it.
2. Burn the candle for a few minutes.
3. Carefully place the jar or glass over the burning candle until the flame goes out.
4. Weigh the candle (including the melted wax and soot) and the jar/glass.
* Observation: The total weight before burning will be the same as the total weight after burning. This demonstrates that even though the candle has changed forms (wax to soot, gas, etc.), the total mass remains the same.
2. The Dissolving Salt Experiment
* Materials: Salt, water, beaker, balance scale
* Procedure:
1. Weigh the salt and the beaker separately.
2. Add the salt to the beaker and weigh the combined weight.
3. Add water to the beaker and stir until the salt dissolves.
4. Weigh the beaker with the salt solution.
* Observation: The total weight before dissolving will be the same as the total weight after dissolving. This shows that even though the salt is no longer visible, it hasn't disappeared; it has simply changed state from a solid to a dissolved form within the water.
3. The Baking Soda and Vinegar Reaction
* Materials: Baking soda, vinegar, balloon, bottle
* Procedure:
1. Add vinegar to the bottle.
2. Add baking soda to the balloon.
3. Carefully stretch the balloon over the bottle's opening (make sure the baking soda doesn't fall in yet).
4. Lift the balloon to let the baking soda fall into the vinegar.
* Observation: The mixture fizzes and the balloon inflates. This is because the baking soda and vinegar react to form carbon dioxide gas, which fills the balloon. While the ingredients have changed, the total mass of the system remains the same. The weight of the bottle, balloon, and gas equals the original weight of the ingredients.
Important Note: These demonstrations may have slight variations in weight due to factors like evaporation, but the overall principle remains true - matter is conserved.
