Properties and Changes of Matter

Properties and Changes of Matter

Unit One

Chapter 2

Properties of MatterProperties of Matter

• What is Matter?– Anything that has mass and takes up space

• What is mass?– Amount of matter an object contains

Types of Matter Types of Matter

• Substance– Matter that has definite and uniform composition

• Mixture– Physical blend of two or more substances that

can be separated using physical means. • Filtration• Distillation

Types of MatterTypes of Matter

More than one type of

“stuff” together

One type of “stuff”

Types of SubstancesTypes of Substances

• Elements– Simplest form of matter

• Compounds– composed of more than one type of atom– Can be separated into simpler substances by

chemical means

Types of MixturesTypes of Mixtures

• Heterogeneous – Multiple phases

• Homogeneous– All in a single phase

Homogeneous Mixtures are SolutionsHomogeneous Mixtures are Solutions

• Solvent– The substances that does the dissolving – Present in the greater amount

• Solute– The substances that gets dissolved– Present in the smaller amount

Heterogenous or HomogeneousHeterogenous or Homogeneous

• Saltwater• Spaghetti sauce• Muddy water• Cough syrup• Salad• Brass

Physical Properties of MatterPhysical Properties of Matter– Quality of a subtance that can be observed or measured without

changing the substance• Melting/boiling point, color, density. Mass

Types of Physical PropertiesTypes of Physical Properties

• Two types of Physical Properties– Intensive

• Are constant regardless of the amount of the substance

– Melt. Pt/Boil. Pt– Density

– Extensive• Vary depending on amount of substance present

– Mass– Volume

• Intensive properties are inherent to a substance and can aid in identifying an unknown sample

Phases of MatterPhases of Matter

• 3 common phases–Solid

•Definite shape•Definite volume•Highly rigid and organized – particles vibrate around fixed points•Nearly incompressible, does not flow

–Liquid•Definite volume•Indefinite shape•Fluid – takes the shape of its container, slightly compressible

–Gas•Indefinte shape – •Indefinite volume•Very fluid - takes shape and volume of containter•Particles move randomly with high energy, very compressible

solid

Additional Phases of MatterAdditional Phases of Matter

• Bose-Einsten Condensate – Exists as temperatures approach absolute

zero (-273 °C)

– Extremely dense, but less structured than solid

• Plasma– Energy similar to gas

– Contains ions rather than atoms• Attraction of ionic charges pull molecules

closer together than in gas

Definitions related to changes in MatterDefinitions related to changes in Matter

• Vapor– Gaseous state of a substance that is in the

liquid or solid state at normal temperatture

• Temperature– Average kinetic energy of the particles

(atoms, molecules, etc.) of the substance

Physical Changes to MatterPhysical Changes to Matter

• Changes that do not alter the chemical compostion

•Change in size or shape

•Change in phase

Chemical Properties of MatterChemical Properties of Matter

• Ability of a substance to react and form a new substance

–Can only be observed or measured by changing the substance into a different substance

Chemical Changes to MatterChemical Changes to Matter

• Results in the formation of a new substances– A chemical reaction takes place

• Evidence that a chemical reaction has taken place– Change in energy

• Temperature increase or decrease– Production of a gas

• Formation of bubbles or detection of odor– Formation of a precipitate

• Presence of a solid– Color change

Chemical ReactionsChemical Reactions

• One or more substances change into a new substance

–Reactants• The substances that exist before the

reaction/chemical change takes place

–Products• The substances that form as a result of

the reaction/chemical change

Evidence of a Chemical ReactionEvidence of a Chemical Reaction• Formation of a gas

• Formation of a solid (precipitate)

• Color change

• Change in energy (absorbed or given off)

Practice: classify the following as physical or chemical properties of waterPractice: classify the following as physical or chemical properties of water

1. Colorless

2. Changes from a liquid to a gas at 100ºC

3. Decomposed by electricity into hydrogen and oxygen

4. Freezes at 0 ºC

5. Produces acetylene gas when dropped in calcium carbide

6. Produces a gas when reacted with sodium

Practice: Classify the following as physical or chemical changes:Practice: Classify the following as physical or chemical changes:

1.Bending a piece of wire into a new shape

2.Cooking a steak

3.Cutting the grass

4.Souring of milk

5.Burning coal

6.Dissolving sugar in water

7.Growing grass

8.Stretching a rubber band

Law of Conservation of MassLaw of Conservation of Mass

• The amount of matter present before the reaction takes place will equal the amount of matter at the completion of the reaction

Food for Thought:Food for Thought:

If 4.0 g of hydrogen are combined with a mass of oxygen to make 36.0 g of water, how many grams of oxygen were used in the reaction?