Describing Matter

Matter

• Anything that has mass and takes up space.

• AKA: “Stuff”

Chemistry

• The study of the properties and changes of any type of matter depends on its makeup.

• Substance is a single kind of matter that is pure

• Pure meaning it always has a specific makeup or composition.

• Example: Table Salt, sugar

Properties

• Physical and Chemical

Physical Properties

• A characteristic of a Pure Substance that can be OBSERVED without changing it into another substance.

• Ex: Using your senses…color, melting, freezing, shiny…

Chemical Property

• A characteristic of a pure substance that describes its ability to change into a different substances.

• AKA: You must try to change it to another substance….Burning, exploding, fizzing.

Elements

• A pure substance that cannot be broken down into any other substance by chemical or physical means.

• Elements are the simplest substances.

Atom

• The basic particle from which all elements are made

• Chemical bond: Force of attraction between two atoms.

• Molecules: Groups of two or more atoms held together by chemical bonds.

Compounds

• A pure substance made of two or more elements chemically combined in a set ratio.

• A compound may be represented by a chemical formula: ratio of atoms.

• When elements are chemically combined, they form compounds having properties that are different from those of the uncombined elements.

Mixtures

• Made of two or more substances

• Each substance in a mixture keeps its individual properties. Also, the parts of a mixture are not combined in a set ratio.

• Two types of mixtures: Heterogeneous and Homogeneous mixtures

Heterogeneous Mixtures

• Hetero…Means Different

• You can see the different parts

• Uneven ratio of substances

• Ex: Soil, granite, Trail mix

Homogeneous Mixtures

• Homo….means same

• Evenly mixed that you can’t see the different parts

• Sugar water, vinegar, Kool Aide…A solution is an example. Doesn’t have to be a liquid: Gold, Air

Separating Mixtures

• Lots of different techniques: Magnets, filters, picking/sorting, distilling, evaporating ect..

Answer Questions on page 15

• 1,2,3

King/SI and his measuring system

LengthKing: (feet, inches, miles)SI: (meter)WeightKing: (ounces, pounds, tons)SI: (gram)VolumeKing: (ounces, pint, gallon, cups)SI: (liter)

Measuring Matter

• Riddle: What weighs more, a pound of feathers or a pound of sand?

Weight and Mass

Weight: a measure of the force of gravity on you. This force can change based on location. Ex: Earth, Jupiter, Moon, Top of the mountain…

Mass: The amount of matter in an object. Unlike weight, mass DOES NOT change with location. Same anywhere.

Units of Mass

The SI (Metric) units is the gram (g), but we use the kilogram (kg), because a gram is so small. (a penny is about 2grams). There are a thousand grams in 1 kilogram.

Volume

The amount of space that matter occupies.

EX: The size of the container. How big or small the cup is.

SI units: Liter, milliliter, cubic centimeters (cm3).

Formula for finding Volume: Length(x)Width(x)Height…LxWxH It will be in cubic (3).

Density

Relates the mass of a material in a given volume. Aka: How much “stuff” is in a given area.

Formula: Density= Mass/Volume

Mass of a block = 200 g

Volume of a block=250 cm3

D=m/v 200/250= 0.80g/cm3

Do question on page 20 1-4

• 1. What is mass?• Why is mass more useful than weight for measuring

matter?• 2. What property of matter is measured in cubic

centimeters?• How are milliliters related to liters?• A plastic box is 15.3cm long, 9.0cm wide and 4.5cm

high. What is its volume?• What measurements must you make to find the density

of a sample of matter?• How can you determine whether a solid substance is

more dense or less dense than water?• Propose a way to determine the density of air.

Calculating Density

• A piece of metal has a volume of 38cm3 and a mass of 277g. Calculate the density of the metal, and identify it based on the information below.

• Iron 7.9g/cm3 Tin 7.3g/cm3

• Lead 11.3g/cm3 Zinc 7.1g/cm3

Physical and Chemical Changes

• Physical Change: Any change that alters the form or appearance of matter but does not make a new substance.– Changes of State: Solid, liquid, gas

• Ex: Ice melting,freezing,evaporating..still water

Changes in Shape: Dissolving, breaking, crushing

Ex: Sugar and water, can be crushed…still the same…….. Adriana was here (:

Chemical Change

• A chemical change or a chemical reaction is a change in matter that produces one or more new substances.

• Unlike a physical change, a chemical change produces new substances with properties different from those of the original substances.

• Ex: Combustion (Gas,oil,or coal burning)• Electrolysis (Breaking down water into hydorgen

and oxygen)• Oxidation (Rusting of an iron fence)• Tarnishing (Tarnishing of silver)h

Law of conservation of mass

• Matter is not created or destroyed in any chemical or physical change.

• Ex: A candle appears to “go away” when it is burned or water when it’s boiled.

• 1770 French Chemist Antoine Lavoisier carried out an experiment to prove that matter wasn’t created or destroyed.

Matter and Thermal Energy

• Energy: the ability to do work or cause change.

• Every chemical or physical change in matter includes a change in energy.

• Ex: Ice melts it absorbs energy• Water Freezes it releases energy

Temperature

• Measure of the average energy of random motion of particles of matter. AKA: How fast particles are moving.

• Faster warmer, Slower cooler

Thermal Energy

• The total energy of all the particles in an object…warm or cool.

• Thermal energy always flows from warmer to cooler matter…. “HighLow” Cup of hot tea flows from the cup to your hand.

• Thermal energy is also known as “heat.” There is no such thing as “Cold,” only an absence of heat.

Two types of changes in Matter

• Endothermic Change: A change in which energy is taken in. Ex: Ice on your forehead, Ice Packs

• Exothermic Change: Energy is released. Ex: Warming your hands next to a fire…Contact Glue, chemical fires

Do questions on page 27

Two types of Energy

• Energy is the ability to do work

• Two main types of energy– Kinetic – The energy of motion

• Dependent on an object’s mass and speedFootball player (Stephen Jackson)Elephant and

bullet

– Potential - The energy that is stored (as a result of position or shape) “Position and Condition”

Types of Potential Energy

• 1) Gravitational

• 2) Chemical

• 3) Electrical

• 4) Nuclear

Types of Potential Energy

• 1) Gravitational – Potential Energy that depends on an object’s

height.• Increases as the object is raised to a higher level.

– Falling objects release energy which can do work

Types of Potential Energy

• 2) Chemical – Chemical energy is the energy stored in the

chemical bonds in compounds.

– When these bonds are broken, the released energy can do work.

– All chemical compounds, including fuels such as coal and gasoline, store energy.

Types of Potential Energy

• ) Electrical – Electrical energy is the energy associated with electric

charges.

– Electric charges can exert forces that do work. • Batteries, which convert chemical energy to electrical

energy, are used to operate portable CD players, flashlights, and calculators.

– Electrical energy also occurs in nature. The powerful bolts of lightning are produced by electrical energy

Types of Potential Energy

• 4) Nuclear Energy– Nuclear energy is the energy stored in atomic nuclei

• The nucleus of an atom is held together by strong and weak forces, which can store an enormous amount of potential energy.

– Nuclear fission (splitting nuclei apart) is used in a nuclear power to generate electricity and do work

– Nuclear fusion (when less massive nuclei combine to form a more massive nucleus) releases energy that can do work as well

• The heat and light of the sun are produced by fusion of hydrogen nuclei into helium nuclei

Energy Transformations

• Energy is constantly changing from one form to another

Energy TransformationsSolar Energy

Collected by Photovoltaic cells

Transforms solar energy into Electrical

Law of Conservation of Energy

• The Law of the Conservation of Energy– States that energy is neither created nor

destroyed.• When energy is used it does not disappear it simply

changes from one form to another.

THE END

• BY:

• Maria Alfaro

• Barbara Gastelum

• Christian Lopez

• Joel Duarte

• Makayla Boston