Law of Conservation of Mass

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I can define the Law of Conservation of Mass so that I can determine if examples given follow the rule.

https://www.youtube.com/watch?v=i2OE9ljBKD8

• A Physical Change happens when a substance ​changes but no new substance is formed.

• ​Physical Change occurs when the state of a substance changes.

• Freezing

• Evaporating

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​Examples include: Water Freezing, Cutting Paper, Melting Butter, Breaking Glass

​A Chemical Change Occurs when a new substance is formed.

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​Indications that a new substance has formed (Chemical Change):

• A change in color

• Formation of Bubbles

• ​Temperature changes

• ​Forms a gas

​Examples of a Chemical Change: Wood burning, A nail rusting, Food Rotting.

​Open System- Allows matter and energy to flow in and out freely.

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Ex. Baking bread in an oven, Melting ice in a pan

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​Closed System- matter or energy is unable to go in or out.

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​Ex. A cup of coffee with a lid on it, Cooking dinner in a pressure cooker

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​Antoine Lavoisier - "Revolutionized Chemistry"

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• ​Lavoisier discovered that "Mass can not be created or destroyed" by carefully measuring the product and reactants in many of the chemical reactions he was researching.

• ​Law of Conservation of Mass states that: "Mass can not be created or destroyed"

​RAP = Reactants Arrow Products

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​Reaction between Methane and Oxygen :

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​All of the atoms that were present at the beginning of the reaction (reactants) are still present in the products. They have just been moved around or transformed!

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