Chemistry

Unit 2: Matter Unit Overview: 1) Classification of Matter 2) Physical and Chemical Properties 3) States (phases) of Matter 4) Phase Changes 5) Density

Quarks(protons & neutrons) & Leptons(electrons) What is Chemistry? Organism Organ Systems Organs Tissues Cells Organelles Molecules Atoms Subatomic particles Quarks(protons & neutrons) & Leptons(electrons) Strings?

Key Vocabulary Chemistry- the study of matter and the changes it undergoes. Alchemy- the attempt to make gold(Au) from other elements. Chemistry arose from alchemy. Matter- anything with mass and volume. Volume- the space occupied by an object.

II. Properties of Matter Physical Properties of Matter- a quality of substance which can be observed without changing the substance’s chemical composition. Examples: color, texture, malleability, ductility, solubility, mass, volume, density, viscosity, conductivity, magnetism.

Physical Properties: Vocabulary Color- the wavelength of light reflected by matter. Malleability- the ability of matter to be hammered into thin sheets, without crumbling. Ductility- the ability of matter to be drawn into wires. Solubility- the ability of matter to dissolve into another substance. Mass- the amount of matter an object contains. Volume- the space occupied by matter. Viscosity- the resistance of a liquid to flow.

Extensive and Intensive Physical Properties(Pre-AP) Extensive Physical Properties- all phys. prop. which depend entirely on the amount of matter present. Ex: mass, volume, length, weight Intensive Physical Properties- all phys. prop. which depend entirely on the identity of matter. Ex: density, color, malleability, texture, magnetism, melting & boiling point.

Chemical Property of Matter- the ability of a substance to undergo chemical reactions to form new substances. (Chemical bonds are formed, broken, or simply rearranged.) When matter undergoes a chemical change, it is called a reaction. Most reactions are permanent. Law of conservation of mass- during a reaction matter is neither gained nor lost, the only thing that changes is how the atoms are held together.

Physical or Chemical Change? Physical Changes: Change in state(melting, freezing, boiling, condensation) Change in shape or form Dissolving a substance in another Chemical Changes: Change the identity of matter --burning, rusting, bleaching, digesting, rotting, cooking

Physical or Chemical Change?

Physical and Chemical Changes

EOC QUESTION!

EOC QUESTION! 40 In the procedure shown above, a calcium chloride solution is mixed with a sodium sulfate solution to create the products shown. Which of the following is illustrated by this activity? F The law of conservation of mass G The theory of thermal equilibrium H The law of conservation of momentum J The theory of covalent bonding

How can we determine if a chemical change is occurring? Indicators of a chemical change!!!! When 2 or more substances are combined it should be a chemical change if we observe: Light or heat is given off Color change Formation of a gas Formation of a precipitate (ppt.) Combustion

Hindenburg 1937

III. States(phases) of Matter Matter exists in 4 States(Phases) 1) Solid-definite shape and volume 2) liquid- indefinite shape but definite volume 3) gas-indefinite shape and volume 4) plasma-indefinite shape and volume with charged particles

What’s the difference between states of matter What’s the difference between states of matter? Solids- particles do not move around, they merely rotate and vibrate, caused by strong bonds or intermolecular forces of attraction. Liquids- particles flow past each other, rotate and vibrate, weaker IMF’s. Gases- particles are very far apart, occupying entire volume of container, they rotate vibrate and collide with eachother, very weak IMF’s.

EOC QUESTION! Which state of matter is the most easily compressed? A Solid B Liquid C Gas D Solution

CHANGES IN STATE OF MATTER Melting: ______ to ______ Freezing: _____ to ______ Boiling: _____ to _____ Condensation: ______ to _____ __________: solid to gas(vapor) __________: gas(vapor) to solid

States of matter: Phase Diagram for H2O (Pre-AP)

States of matter: Phase Diagram for CO2 (Pre-AP)

Heating Curve for Water 120 °C steam 100 °C water  steam 50°C liquid water 0 °C ice liquid -10 °C ice Heat added 

://www.kentchemistry.com/links/Matter/HeatingCurve.htm

Cooling Curve of Water

Supercooled Water Trick!

Supercooled Water Trick! http://www.cleanvideosearch.com/media/action/yt/watch?videoId=lISK1YFcZBM http://www.cleanvideosearch.com/media/action/yt/watch?videoId=iHqNh8QqIrU&name=Supercooling+%26+Snap+Freezing+Example+Dec+2010&uploadUsername=johnmhoyt&hitCount=917 http://www.cleanvideosearch.com/media/action/yt/watch?videoId=chaD2J-J4o0

V. Density Density- mass divided by volume. Water has a density of 1g/mL Matter which is less dense will float on matter which is more dense will sink.

Measuring Density

Density Practice Problems 1) Find the density of an 8.1gram wood block with a volume of 2.43cm3. 2) Find the density of a 0.03582 liter liquid with a mass of 0.082 kg. 3) What is the mass of a 1.3cm3 of glass, if the density of glass is 2.60g/cm3? 4) Find the volume of a cube with a mass of 2.28g and a density of 0.886 g/ml. 5)The density of a block of metal is 7.40 g/cm3. Find the mass of a 1.55 cm3 block.

Radioacitivity(Pre-AP) Nuclear Radiation- tiny particles or energy given off(emitted) or absorbed by the nucleus of an unstable atom. 3 types of nuclear radiation: Alpha particle(largest) Beta particle (medium size) Gamma ray (not matter, energy)

Characteristics of Radiation penetrating Particle symbol/formula composition mass power Alpha Beta positron Gamma

http://www.teachertube.com/viewVideo.php?video_id=105795

Nuclear Radiation: Penetrating Power

End of Unit 2 Review tomorrow Test the following day Density Lab Begin Unit 3