EARTH CHEMISTRY

INTRODUCTION What is matter?____________ ____________________________________________________________ What is a crystal?_____________ __________________________________________________________________________________________ What property of hornblende does this photograph show?_________ Hornblende a silicate mineral . Hornblende and other silicates make up 95 percent of the Earth’s crust. The basic building block of most minerals , including hornblende, is a pyramid-shaped unit consisting of a silicon atom surrounded by 4 oxygen atoms. Minerals differ because of the other types of atoms they contain and the way in which the silica units are joined.

QUESTION??? How does the arrangement of atoms determine a mineral’s properties? A: _________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

WHAT IS MATTER? MATTER is _____________ ______________________________________________________________________________ All matter on Earth and in the universe occurs in what four forms? ________________________ _______________________ _________________________ __________________________ Q: When your skin is wet, even on a hot day, it usually feels cool- especially if it is windy. How can warm air feel cold?

SOLIDS Solids are substances with ______ Packed particles. Most solids are _______________ _________________ because the particles are arranged in _______ _______________ ____________ Looking at the picture of granite you can see the individual crystals of quartz, mica and feldspar. This crystalline structures have a definite shape and volume.

CRYSTALS Perfectly formed crystals are rare. Many crystals form in the same place at the same time . Crowding prevents the formation of perfect shapes. The result of this mass of crystals are called _________________ ___________. Most solid substances on Earth are ______________ ______________. Example : granite on the previous slide is an example of a poly crystalline solid. Some solids have no regular internal patterns _________ is a solid that consists Of densely packed atoms arranged randomly. Glass is formed when molten material is cooled so rapidly that atoms do not have enough time to arranged themselves in a regular pattern. This type of solid does not form crystals.

LIQUIDS At any temperature above absolute zero the atoms in a solid _________________. Because these vibrations increase with increasing temperature they are called ________________ ______________________. At the _____________ ________ Of the material these vibrations become vigorous enough to break the forces holing the solid together. The particles can then slide past one another and the substance will then become a ______________ Liquids take the shape of the _____________ they are placed in Liquids do have a ____________ ________________

GASES When particles in a liquid vibrate vigorously some particles may gain sufficient energy to ___________ the liquid. This process of a change from a liquid to a gas at temperatures below the boiling point is called ________________________ When liquids reach the boiling point it vaporizes quickly as a gas. In gases the particles are ______ By relatively ________ distances. They travel at high speeds in one direction until they bump into one another Gases have no _________ _______ Or _____________ They can be restrained by a container or the _________ of _____________

Force of gravity Earth’s gravity keeps gases in the atmosphere from escaping into space.

PLASMA When matter is heated to a temperature greater than 5,000 degrees C the collisions between the particles are violent. The collisions knock the electrons away from the atoms. These extreme temperatures only exist in stars so the gases in stars consist entirely of positive ions and free electrons. These hot highly ionized gases are called ___________ On earth lightning and neon are in a plasma state

CHANGES OF STATE What is condensation?_______ ____________________________________________________________________________________________________________________________________________________ What is sublimation?________________________________________________________________________________________________________________________________________________________________________

CONSERVATION OF ENERGY DEFINITION__________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Particles that make up matter All matter is made up of substances called __________ What is an element?______ ______________________________________________________________________________ Each element has _________ ____________________. All atoms consist of even smaller particles.

What are the subatomic particles of an ATOM? _____________ tiny particle that has a mass and a positive electrical charge _____________ particle with ~ the same mass as a proton but is electrically neutral _________ has little mass and has a negative charge. What is the electron cloud?___________________ _______________________

SYMBOLS FOR ELEMENTS There are ________ elements that occur naturally on Earth in the stars. Other elements have been produced in the laboratory. Each element is identified by either 1,2 or 3 symbols For example H Ca Uub All elements are arranged according to their ___________ ___________ in the periodic table of elements

MASS NUMBER Mass number is the sum of the protons and neutrons Because electrons have little mass they are not included in the mass number The number of P and N in atoms varies widely in different elements.

ATOMIC NUMBER The number of protons in an atom’s nucleus is the atomic number

ISOTOPES Atoms of the same element that have different _______ _______________. Example : Radioactive isotopes: isotopes where the nuclei is unstable and tend to break down When they breakdown they will release radiation

ENERGY LEVELS Electrons exist in Energy levels The size of an atom is determined by the _________ and __________ of its electrons Electrons are distributed over more than one energy level. Electrons move very fast around the energy level Each energy level can hold only a limited number of electrons 1st energy level _______ 2nd energy level _________ 3rd energy level ___________ 4th energy level __________ Depending on the element it could have as many as 7 energy levels.

VALENCE ELECTRONS What are Valence electrons? _________________________ _________________________ _________________________ _________________________ _______________________

WHAT IS AN ION? IONS atoms that gain or lose and electron has a net electrical charge. _________________________ _________________________ _________________________ _________________________ _________________________ _________________________ _________________________ _________________________ _________________________ _________________________

What elements are most abundant on Earth and in the universe. The most abundant elements in the universe are greatly different from most of the elements on Earth/ In the Universe ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- In the Earth’s Crust ___________________________________________________________________________________________________________________________________________________________________________________________________________________