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Explore the concept of mass and its conservation through a series of experiments involving changes in shape, melting, burning, and dissolution. Record and analyze results to understand the law of conservation of mass.
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Mass What is mass? How can it be measured?
Mass and Change Lab • Goal- What happens to the mass of an object when they are changed? Part 1: Change the shape of steel wool Part 2: Melting ice Part 3: Burning steel wool Part 4: Dissolved sugar in water Part 5: Dissolved Alka-Seltzer
Data The lab groups should report their results on the post-it on the board so that the entire class data can be recorded. Change should be recorded as + (for a gain) or – (for a loss).
Law of Conservation of Mass • This law was developed by a French chemist named Antoine Lavoisier. • Lavoisier carefully measured the mass of the reactants and products when carrying out chemistry experiments. • He noticed that in every case, the mass of the reactants was ALWAYS equal to the mass of the products.
Law of Conservation of Mass • Historical Context- Year was 1776. • He was the first scientist to recognize and name the elements hydrogen and oxygen. • In 1789, he wrote the first chemistry textbook. • Oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc and sulphur (list also included 'light' and 'caloric‘). • He was executed, along with hundreds of other nobles, during the French Revolution.
Law of Conservation of Mass Key Concept 1: The law of conservation of massstates that mass is neither created nor destroyed in a chemical reaction, it is conserved. The mass of the reactants equals the mass of the products. massreactants = massproducts
What is this Matter? • Matter is anything that takes up space and has mass. • Water • Rocks • Air • Wood • Plastic • You • So what not matter?
Matter is….. c • Key Concept 2: Matter is anything made of atoms. • Matter has observable and measurable qualities. • Key Concept 3: Two basic types of properties of matter: physical properties and chemical properties. • Key Concept 4: All matter can undergo change: physical change or chemical change
White Board Properties Change
Properties • Key Concept 5: Physical properties can be observed without changing the substance(use your senses). • Key Concept 6: Chemical properties are determined by trying to change the make-up of a substance (only evident at the particle level).
Change • Key Concept 7: Physical change- the original substance still exists (its particles are still the same); it has simply changed form. • Key Concept 8: Chemical change- takes place on the molecular level and produces a new substance (chemical changes are accompanied by physical changes) (hard to undo).
Examples Chemical Properties Physical Properties Physical Change Chemical Change
Exit Pass: Physical(PC) or Chemical Change(CC) • Part 1: ____ Change the shape of steel wool • Part 2: ____ Melting ice • Part 3: ____ Burning steel wool • Part 4: ____ Dissolved sugar in water • Part 5: ____ Dissolved Alka-Seltzer