It’s the Law Lab - Grading

• Introduction: • Describe the law of conservation of mass. (1pt)

• Matter can’t be creted or destroyed• Same # of atoms on both sides• Mass should be the same on both sides

– Write the chemical equation for the reaction and explain what the reactants and products will be in the lab• Mixing vinegar & baking soda to get sodium acetate, water

and carbon dioxide– Reactants:_vinegar & baking soda_________ (.5 pt)– Products: _sodium acetate, water, carbon dioxide______

• Vinegar + baking soda sodium acetate + water + carbon dioxide (.5 pt)

It’s the Law Lab continued…

• Safety: (1pt)– Goggles– Glassware

• Problem: (1 pt)– How does the mass of several chemicals change

when mixing a chemical reaction for a closed system?

– For an open system?

It’s the Law Lab continued…• Hypothesis: “If the reaction is in a closed system then …”– “If the reaction is in an open system then…”– Discusses the mass staying the same or changing (.5 each)– If…then statement (.5)– Wrote why or because they thought that way (.5)

• Variables: (1 pt)– IV: Type of system– DV: Mass of the reaction– Constants: same amt of baking soda, vinegar, same brand,

same flask, t.b.b

• Don’t worry about materials & procedures

Data Table

• Measurements have units (-.5 each)• Open system should have less mass (-1)• Closed system should not have less than .5g

less (-1)

Data Table

It’s the Law Lab

• Error Analysis: (1 pt)– Include any important factors that you think may

have actually affected your results

• I will grade the questions