MATTERMATTER

What is Matter?What is Matter?

Must have Must have massmass

Occupies space (has Occupies space (has volumevolume))

DensityDensity

Because all matter has mass and Because all matter has mass and volume, all matter has density.volume, all matter has density.

D D = = MM

VV

Law of Conservation of MatterLaw of Conservation of Matter

Matter cannot be Matter cannot be created or created or destroyeddestroyed

When 400 grams of When 400 grams of wood are burned only wood are burned only about 30 grams of about 30 grams of ash remain. ash remain.

What happened to the What happened to the missing matter?missing matter?

During a During a chemical chemical reaction reaction matter is matter is conservedconserved

States of MatterStates of Matter

Matter can Matter can exist in three exist in three basic states:basic states: Solid (s)Solid (s) Liquid (l)Liquid (l) Gas (g)Gas (g)

A Fourth State of Matter?A Fourth State of Matter?

PlasmaPlasma Occurs when the Occurs when the

atoms of matter have atoms of matter have been stripped of their been stripped of their electrons.electrons.

Basic Types of MatterBasic Types of Matter

Pure SubstancesPure Substances

ElementsElements

ElementsElements

• Made up of atoms of one specific typeMade up of atoms of one specific type

• Cannot be broken down further by a Cannot be broken down further by a chemical reactionchemical reaction

• Have specific physical and chemical Have specific physical and chemical properties.properties.

The Periodic Table of ElementsThe Periodic Table of Elements

• Each element has its Each element has its own atomic numberown atomic number

• Atomic number tells Atomic number tells us the number of us the number of protons in that protons in that elements nucleus.elements nucleus.

Examples of ElementsExamples of Elements

What elements can you find in the What elements can you find in the classroom now?classroom now?

What elements are What elements are important in the food important in the food we eat?we eat?

Where Do We Get Elements?Where Do We Get Elements?

Obtained in Obtained in nature in their nature in their pure state.pure state.

Some elements Some elements are combined are combined together in together in compounds and compounds and are separated are separated out through out through chemical chemical reactions.reactions.

Some elements don’t Some elements don’t exist naturally, and exist naturally, and are man-made are man-made through nuclear through nuclear bombardment bombardment reactionsreactions

Elements and Their SymbolsElements and Their Symbols

Elements have either Elements have either one or two letters one or two letters when they are written when they are written as a symbol.as a symbol.

If two letters, the If two letters, the second letter is second letter is written lower case. written lower case. (Ex: Write Cu for (Ex: Write Cu for copper not CU)copper not CU)

Usually it is pretty easy to match an Usually it is pretty easy to match an element to its symbol (Ex: Neon = Ne)element to its symbol (Ex: Neon = Ne)

Sometimes the symbol is derived from a Sometimes the symbol is derived from a Latin name for the element.Latin name for the element.Ex: Au = gold (comes from Latin word aurum) Ex: Au = gold (comes from Latin word aurum)

Tricky ElementsTricky Elements

Here are some of the Here are some of the harder elements to harder elements to match their name to match their name to their symbol.their symbol.

Na = sodiumNa = sodium K = potassiumK = potassium Fe = ironFe = iron Cu = copper Cu = copper Sb = antimonySb = antimony Sn = tinSn = tin Pb = leadPb = lead Hg = mercuryHg = mercury W = tungstunW = tungstun Au = goldAu = gold Ag = silverAg = silver

Phases and ElementsPhases and Elements Under standard conditions, Under standard conditions,

most elements exist as solids.most elements exist as solids.

The Gases: The Gases: H, He, Ne, Ar, Kr, Xe, Rn, H, He, Ne, Ar, Kr, Xe, Rn,

O, F, ClO, F, Cl

The Liquids:The Liquids: Hg, BrHg, Br

Diatomic ElementsDiatomic Elements

Two atoms of the Two atoms of the same element joinedsame element joined

Bromine, Iodine, Bromine, Iodine, Nitrogen, Chlorine, Nitrogen, Chlorine, Hydrogen, Oxygen, Hydrogen, Oxygen, FluorineFluorine

BrINClHOFBrINClHOF

CompoundsCompounds

CompoundsCompounds

Most elements in nature do not exist in Most elements in nature do not exist in their pure state, but in compounds.their pure state, but in compounds.

Compound = Two or more different elementsCompound = Two or more different elements

bonded together bonded together chemicallychemically

Ex: CEx: C66HH1212OO66, MgCl, MgCl22, CH, CH44, NO, NO22, CO, CO22, NaCl, NaCl

Law of Definite ProportionsLaw of Definite Proportions

• Elements in compounds Elements in compounds have definite fixedhave definite fixed

proportions by mass.proportions by mass.

Getting New PropertiesGetting New Properties

Compounds have different chemical and Compounds have different chemical and physical properties than the elements that physical properties than the elements that make them up.make them up.

- Sodium (Na)- Sodium (Na)

Toxic, reactive metal Toxic, reactive metal that will explode in that will explode in waterwater

- Chlorine (Cl)- Chlorine (Cl)

Brown toxic gas that Brown toxic gas that was used as a was used as a chemical weapon to chemical weapon to kill people in WWIkill people in WWI

Sodium Chloride (NaCl)Sodium Chloride (NaCl)

White edible crystal, White edible crystal, and salt for my french and salt for my french fries!!fries!!

Focus QuestionFocus Question

What are the differences between What are the differences between elements and compounds?elements and compounds?