Lesson 2



LESSON 2.  Conservation of Matter - Lab




baking soda

beaker (100 ml)

effervescent tablets

electronic scale (or triple beam)

Erlenmeyer Flask (250 ml)

graduated cylinders


measuring spoons (ml)



zip lock baggies


Objective: Understanding the nature of matter.


Teacher Notes:


Ask students "Do you think matter can be created or destroyed?"  If it can't be created where does it come from? Then ask if matter can be destroyed why do we still have any matter left?  Where does it go? Understanding matter is not easy.


In this experiment students will test several changes of states of matter to determine if mass is created or destroyed during reactions. This lab allows students to discover the law of conservation of matter through simple experiments which sometimes goes against their "obvious" prediction.  This will help them to remember and explain why matter cannot be created or destroyed.


Go over directions in the readings to assure they understand how to keep a closed system so gases do not escape.  Note you can adjust the amounts by what you may have on hand. 



In all the reactions used in this experiment the total amount of mass before and after should be the same.  However, depending on how careful the students are will depend on the end results.  You can use different amounts, depending on the precision of your scale or triple beam balance.  If you use a triple beam balance, make sure the students know how to read them.


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