Conservation of Matter Introduction

Conservation: Retaining what you have from the beginning to the end Matter: Anything that has mass and takes up space

The conservation of matter means the amount of matter you start with is the amount of matter you need to end with and if you do not… Then you need to figure out where the matter went.

Open system: the reaction that has occurred is open to the room Closed system: the reaction is isolated (closed off) from the room

Terminology and Symbols Equations Terminology and Symbols

Reactants These are the compounds that will react. They are always found before the arrow.

Products These are the compounds created after the reaction occurred. They are found after the arrow.

The arrow The arrow means the reaction yields.

Items Above the Arrow Anything written above the arrow is a catalyst. A catalyst is anything that participates in the reaction but it is not consumed.

A catalyst A catalyst is used to speed up a reaction. It lowers the amount of energy required to start the reaction.

Examples of Reactions with Catalysts

(aq) The aq stands for aqueous. Aqueous means water and therefore anything written before the aq is in water

(s) This symbol is also found after a product or a reactant. It means the compound is a solid.

(l) This symbol is found next to a product or a reactant. It means the compound is a liquid.

(g) This symbol is found after a product or a reactant. It means the compound is a gas.

λν These symbols are found above the arrow. The catalyst used was light.

 This symbol is found only over the arrow. It shows the catalyst used was heat.

Catalyst Light and heat are just two types of catalysts. Compounds and surfaces can also be used as catalyst. (ex: H2)

Coefficients These are numbers found in front of the compounds. They tell us how many of these compounds react or form in the equation.

Did it react? Five things to look for to determine if it was a chemical reaction or just a physical change

Five Things that Might Suggest it Reacted The temperature of the beaker increased or decreased (heat absorbed or released) The color of the solution changed (not just faded, but to a different color) You observed bubbles Light was produced A sound was heard

Silver Nitrate and Copper Wire http://www.youtube.com/watch?v=rgYhkVy5cBU Luminol http://www.youtube.com/watch?v=yZOvbho4HiI&NR=1&feature=endscreen