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Matter-anything that has mass and takes up space.  Properties of Matter -Matter can have many different properties or characteristics-Chemistry is the study of the properties of matter and how it changes

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Substance-a single kind of matter that is pure, meaning it always has a specific makeup- or composition- and a specific set of properties.-Every form of matter has two kinds of properties- physical and chemical properties.

-Physical Property- a characteristic of a pure substance that can be observed without changing it into another substance.-Examples of physical properties

-Density, Hardness, Texture, Color, State (solid, liquid, gas)

-Ability to dissolve in water, conductivity, malleability

-Chemical Property- a characteristic of a pure substance that describes its ability to change into different substances.-To observe a chem. prop. you must try to change it.-Examples of chemical properties

-Flammability, Ability to react with oxygen (rust or tarnish) 

What is an Element:-All matter in the universe is made of slightly more then 100 different substances called elements.-Element-a pure substance that cannot be broken down into any other substance by physical or chemical means.-Elements are the simplest substances

Particles of Elements- Atoms-All matter is made of atoms-Atom-is the basic particle from which all elements are made.-Different elements have different properties because their atoms are different.

Separating Mixtures:-Mixtures can be separated into their component parts since they are not chemically combined.-Sometimes it may be difficult but it can be done.-Ways to separate mixtures

-magnets, filters, distilling, and evaporating 

When Atoms Combine:-Atoms of different elements can combine.-Atoms combine to form larger particles named molecules-When atoms combine to form molecules they are connected by chemical bonds, which is the force of attraction between 2 atoms-Example of a molecule versus an atom H2O is made of 3 atoms (2 hydrogen and 1 oxygen atom bonded together to form 1 water molecule) 

Compounds:  -All matter is made of elements but most are not alone in nature.-Compound-a pure substance made of two or more elements chemically combined in a set ratio.-A compound can be represented by chemical formula

ex: H2O or CO2

-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, elements or compounds, that are together in the same place but are not chemically combined.-Each substance keeps it’s properties in a mixture-Mixtures don’t have to be uniform

Types of Mixtures-Heterogeneous Mixture- a mixture in which pure substances are unevenly distributed throughout the mixture.

-Homogeneous Mixture -a mixture in which substances are evenly distributed throughout the mixture.

-You can’t see the parts of a homogeneous mixture

-Solution-a homogeneous mixture in which one substance dissolves in another.

-Solvent-does the dissolving (ex: water)

-Solute-disappears or is dissolved (ex:sugar)

Separating Mixtures-Mixtures can be separated into their component parts since they are not chemically combined.-Sometimes it may be difficult but it can be done.-Ways to separate mixtures

-magnets, filters, distilling, and evaporating 

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Separating Mixtures:-Mixtures can be separated into their component parts since they are not chemically combined.-Sometimes it may be difficult but it can be done.-Ways to separate mixtures

-magnets, filters, distilling, and evaporating 

Changes of State:-States of matter are solids, liquids, and gases.-A change in state is an example of a physical change 

Changes in Shape or Form:-Solutions, where one substance dissolves in another, are an example of a physical change.-Other examples: Bending, crushing, breaking, chopping, and anything else that changes form or shape.-You can separate mixtures by filtering and distilling

Chemical Change- a change in matter that produces one or more new substances-A chem. change produces new substances with properties different from those of the original substances 

Examples of Chemical Changes:-Methane, CH4, when combined with oxygen by combustion, forms CO2 and water vapor.-Other chemical changes are electrolysis, oxidation, and tarnishing.-See chart on Page 70 in book. 

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Conservation of Matter:-Law of conservation of matter- the principle that the total amount of matter is neither created nor destroyed during any physical or chemical change.-“What goes in must come out!!”-The mass of the reactants must equal the mass of the products.-The number of atoms in = number of atoms out

ENERGYThe ability to do work or cause

change.Every chemical or physical

change requires energy. EX. Bending a paper clip

FORMS OF ENERGY

Temperature- a measure of the average energy of random particles of matter

Thermal energy - the total energy of all the particles in an object

Endothermic change- energy is taken in ex. Ice melting

Exothermic change- energy is released ex. Combustion recall whoosh lab

Chemical Energy- energy stored between chemical bonds between atoms

Electromagnetic energy- a from of energy that travels through space as waves. Ex radio waves, x-rays

Electrical energy- the energy of electrically charged particles moving from one place to another ex. electric pickle