CONSERVATION OF MATTER - LAB

PROBLEM:
Can mass be created or destroyed?

HYPOTHESIS:

MATERIALS: 
electronic scale (or triple beam), ice, salt, effervescent tablets, zip lock baggies,  Erlenmeyer Flask,  vinegar, baking soda, beaker, 50 graduated cylinder, measuring spoons (ml)

Do the following and record results on the data chart.

1. When a solid such as salt dissolves in water will the mass increase, decrease or remain the same?
   Use a 100 ml beaker with 50 ml of water; weigh and record.  Measure 5 ml of salt; weigh and record.  Pour the salt into the water and stir.  Weigh and record.   
   What happens?
   
   
    

2. When an effervescent solid change into a gas will the mass increase, decrease, or remain the same?
   Weigh a plastic bag (zip lock) with 50 ml of water.  Weigh and record.   Weigh a portion of an effervescent tablet; weigh and record.  Place the tablet into the plastic bag and let the reaction complete.  Weigh and record.
   What happens?
   
   
    

3. When a solid such as ice changes to a liquid will the mass increase, decrease or remain the same?
   Use a zip lock plastic bag with one or two cubes of ice.  Weigh the bag with ice.  Melt the ice by placing the container in a warm spot or in a tub with warm water.  After the ice melts, weigh and record.  What happens?
   
   
    

4. When there is a chemical reaction from a solid to a gas, will the mass increase, decrease, or remain the same?
   Weigh a 250 Erlenmeyer flask with 2 ml of baking soda.  Measure a balloon and 5 ml of vinegar.   Have a balloon ready to put on the top after you pour in 5 ml of vinegar.  Quickly pour in the vinegar and then put balloon on the top to trap the gas that is escaping.  Swirl the flask until the reaction ends.  Weigh and record.

 CONCLUSIONS:  Did you prove the conservation of mass?  If not, explain some possible problems during the experiments.