Aim: What is matter? What are elements and compounds? What are physical and chemical properties? What are physical and chemical changes? 1. Matter – anything that has mass and occupies some volume. 2. Phases of matter – Solid (s), Liquid (l), and Gas (g) STATES OF MATTER STATES OF MATTER 1. Solids — particles are close together in a fixed position. Have definite shape and volume. 2. Liquids — Particles are spread further than a solid. Liquids take the shape of their container. Definite volume, no definite shape. 3. Gases — Particles are random and far apart. Gases expand to completely fill their container. Gases travel in random straight-line motion. No definite volume, no definite shape. Particle Diagrams Particle Motion Solids Phase Change Answer Key Matter Pure Substance Pure Substance – the composition of the sample is the same throughout. Examples: Elements and Compounds Elements and Compounds Element Made up of 1 type of atom. 2. Cannot be broken down chemically. Can be broken down through nuclear decay. 1. Compound Made of two or more different elements chemically combined in fixed proportions. 2. Can be broken down chemically. 1. Compounds Contain different chemical and physical properties than the elements that compose them in a fixed proportion or ratio. C12H22O11 Fixed proportion by mass in sucrose molecule 12 C 22 H 11 O Compounds are formed a result of chemical reactions of the elements Atoms and Molecules Atom – smallest unit of an element. Contains all the properties of that element. Molecule – two or more elements chemically combined. Types of Molecules Elemental molecules: Made up of 1 type of element. 1. Monatomic 2. Diatomic 3. Triatomic Molecular Compounds: Contain two different types of elements Monatomic vs. Diatomic Molecules Monatomic: Some elements exist as single atoms. He, Ne, Ar, C, Li Diatomic: Molecules that contain one type of atom bonded in a pair. Br2 I2 N2 Cl2 H2 O2 F2 Allotrope Two or more forms of an element in the same phase. 2. Different molecular structures. 3. Different physical and chemical properties. 1. How do we differentiate between chemical and physical changes ? Properties of Matter Physical Property- Property or characteristic that can be observed without changing the chemical makeup of a substance. Conductivity Color Density Boiling point Mass Melting point Volume Phases (S,L,G) Odor Brittleness Luster Malleability Ductility Malleable Ductile Properties of Matter 2) Physical Changes – Change in form, shape, and or appearance of matter, but no new substance is created. All Phase Changes Can you think of any physical changes? Physical Changes Observed change that is not accompanied by a change in chemical makeup.  boiling of a liquid  melting of a solid  dissolving a solid in a liquid Chemical Properties and Chemical Change 3) Chemical Property - property that describes how a substance reacts with, or acts with, another substance. Properties of Matter 4) Chemical Change or chemical reaction – new substances with different chemical properties are produced. Burning hydrogen (H2) in oxygen (O2) gives H2O. Hindenburg Signs of a Chemical Change 1. Heat (released or absorbed) 2. Light (released) 3. Gas Produced (not from boiling!) 4. Precipitate – a solid formed by mixing two liquids together. 5. Color change – only when a new substance is formed. Compounds have different physical and chemical properties than the atoms that compose them. Law of Conservation of Matter Matter is not created or destroyed, in a chemical reaction it is converted to new products with different properties. 2. Atoms cannot be created nor destroyed during chemical and physical changes. 3. The atoms are rearranged. 1. Class take a look!!!!! NaCl(aq) + AgNO3(aq)  AgCl(s) + NaNO3(aq) Regents Questions Regents Questions Regents Questions How can we distinguish between two types of mixtures? 1. Mixtures - combinations of 2 or more substances that can be separated by physical means. The substances are not chemically combined. Examples: Mixtures Homogeneous mixture (solution)  Same properties throughout sample. (1 phase) Heterogeneous mixture  2 or more substances called phases that differ in properties. (2 or more phases) Examples:  Iced tea, Pancake syrup, OJ, Salt water, Brass, Clean air Examples:  Oil and vinegar  Ice + Water  Granite Solutions Mixtures Solutions - consist of a solute dissolved in a solvent a) Solute - substance that is dissolved by solvent b) Solvent – substance that dissolves another (occurs in greater proportion by mass) Examples: Salt water solution: Salt = Solute Water = solvent Can you think of a solution with a solute and solvent? Blood Component Processing - YouTube Mixtures Colloids  Colloids - A colloid is a substance dispersed evenly throughout another substance. Matter Flowchart MATTER yes Can it be physically separated? MIXTURE yes Is the composition uniform? Homogeneous Mixture (solution) no PURE SUBSTANCE no Heterogeneous Mixture yes Can it be chemically decomposed? Compound Element no Separating Mixtures by Physical Means Filtration – separate large particles from a mixture as they pass through a porous substance such as a filter or screen. 2. Distillation – separation of mixtures based on boiling points of the substances in the mixture. 3. Chromatography - separation technique based on the different attractions of two or more substances to a stationary and a mobile phase. 1. How can we distinguish between types of mixtures using particle diagrams? Heterogeneous mixture Homogenous Mixture (solution) Are the pictures above pure substances or mixtures? a. pure – 1 element Explain b.Pure - 1compound c.Mixture – 2 elements d.Pure -1 element e.Pure – 1 compound f.Mixture – 2 compounds, 1 element g.Mixture – 1 element, 1 compound h.Pure – 1 element