What’s the MATTER, Definition, States, and Change of State

MATTER, Definition, States, and Change of State At the conclusion of our time together, you should be able to: 1. Define matter 2. Define the various states of matter and draw an example of each state 3. Recognize that particle motion determines the state of matter

Matter:  Anything that has mass and takes up space Matter is made up of building blocks: atom – smallest unit of an element. element – a pure substance made of only one kind of atom. compound – made of two or more atoms that are chemically combined.

FYI  90% of the Earth’s crust is made up of only 5 elements: Oxygen49.2% Silicon25.7 % Aluminum 7.5% Iron 4.7% Calcium 3.4%

States of Matter  Solid- Definite volume and shape Particles are tightly packed Slight expansion when heated Incompressible

Solid Vibration around fixed points

 Liquid- Has definite volume, but no definite shape (assumes the shape of the container) Particles are loosely packed (can flow by sliding over each other) Easily expand when heated Considered incompressible States of Matter

Liquid Vibration around sliding points

 Gas- No definite shape or volume Expand to fill the container Particles are spaced far apart Compressible States of Matter

Gas Vibration around moving points

 Plasma- Consists of electrically charged particles It’s an ionized gas Common in space, but very rare on Earth Found in lightning, fluorescent lights and neon signs States of Matter

Plasma “Super-heated Gas” When atoms are so hot, they lose ALL of their electrons. When atoms are so hot, they lose ALL of their electrons.

Energy Amounts in States of Matter  Solid- little energy, particles vibrate and rotate  Liquid- more energy, they move freely by sliding over each other  Gas- even more energy, move quickly  Plasma- most energy, move extremely fast

Solid Liquid Gas Plasma Made of Atoms Holds its shape Atoms move past each other

States of Matter Changes of State Solid Liquid Gas Energy

Names of Phase Changes  Solid to Liquid= Melting  Liquid to Gas= Boiling/evaporation  Gas to Liquid= Condensation  Liquid to Solid= Freezing  Solid to Gas= Sublimation  Gas to Solid= Deposition

Boiling Melting Freezing Condensation DepositionDeposition

Matter, Classify Matter At the conclusion of our time together, you should be able to: 1. Classify a mixture of matter based on their physical and chemical properties 2. Characterize various types of matter

Types of Matter  Pure Substance- Matter with a fixed composition It has distinct properties Examples =elements compounds

Types of Matter  Mixtures- Most matter is a mixture The composition is not fixed (changes from sample to sample) Two Types – Homogeneous Heterogeneous

Homogeneous Mixtures  Composition is uniform throughout Solution-  Particle size = 0.01 – 1 nm  Doesn’t settle out upon standing  Can’t be separated by filtering  Doesn’t scatter light  Example = salt water

Heterogeneous Mixtures - Suspension  The sample varies in composition, properties and appearance  No uniformity Particle size is greater than 1000 nm Particles settle out upon standing Can be separated by filtration Might scatter light Examples = soil, trail mix, pond water

Colloid-  Particle size = 1 – 1000 nm  Doesn’t settle out upon standing  Can’t be separated by filtering  Scatters light (Tyndall Effect)  Examples = milk, gelatin, smoke Hetereogeneous Mixtures

Let’s Look at Some Examples:  Mixtures are variable combinations of 2 or more pure substances. Heterogeneous – visibly separate phases Homogeneous – Same throughout

Matter, Classify Changes of Matter At the conclusion of our time together, you should be able to: 1. Characterize various changes of matter 2. Recognize that a change of state in matter is a physical change

Physical Physical Change  A change in matter from one form to another without changing its chemical properties  (most can be reversed)  No change in atoms/molecules

Physical Change  Examples = Change in state or phase change Dissolving Compressing Light emission/absorption Electrons passing through metals

Physical Change More Examples =  boiling of a liquid  melting of a solid  dissolving a solid in a liquid to give a homogeneous mixture  making a solution

Properties  Every substance has a unique set of properties (characteristics that identify that substance)  Physical Properties- Properties that can be measured without changing the identity and composition of the substance

Physical Property Examples- Color Odor Density Melting Point Boiling Point Hardness Solubility

Chemical Chemical Change Bonds are made / broken Change in oxidation states Bonds are made / broken Change in oxidation states Cl Li +1

Examples of Chemical Change  Chemical change or chemical reaction — transformation of one or more atoms or molecules into one or more different molecules. Burning hydrogen (H 2 ) in oxygen (O 2 ) gives H 2 O.Burning hydrogen (H 2 ) in oxygen (O 2 ) gives H 2 O.

Sure Signs of a Chemical Change “Chemists Get Practice Trying Labs”  Color Change  Gas Produced (not from boiling!)  Precipitate – a solid formed by mixing two liquids together  Temperature Change  Light

Chemical Properties  Properties that describe the way a substance may change to form other substances  Only observed when a chemical reaction takes place

Chemical Property Examples  Combustible  Reactive with water or acid  Flammable  Corrosive  Decomposes in air

Remember the Law of Conservation of Mass  In a physical change or a chemical reaction, mass is neither created or destroyed (Antoine Lavoisier)

What’s the MATTER Classify Matter Let’s Put it All Together in a Chart!!

Is the composition uniform? NoNoYes MATTER Can it be physically separated? Homo- geneous Mixture (solution) Hetero- geneous Mixture Compound MIXTURE PURE SUBSTANCE Yes NoNo Can it be chemically decomposed? NoNo Yes Suspensions Element Colloids