Properties of Matter What is matter Matter is

Properties of Matter What is matter? Matter is anything that has mass and volume.

Classification of Matter can be divided into 2 categories: SUBSTANCES & MIXTURES • Substances can NOT be separated into different kinds of matter by physical means. • Mixtures can be separated into different kinds of matter by physical means. 2

Classification of Matter What are substances? In science, substances are limited to elements and compounds. – Elements • Any substance in which all the atoms in a sample are alike, one kind of matter • Examples: Carbon, Sodium and Oxygen – Compounds • 2 or more elements chemically combined in a fixed ratio • Usually has different appearance from elements that make it up • Examples: Water – H 2 O and Salt - Na. Cl 3

Classification of Matter • Atom-smallest possible particle of an element • Molecule- smallest possible particle of a compound 4

Classification of Matter What are mixtures? 2 or more substances that can be separated by physical means Do not always contain the same amounts of the different substances that make them up –Homogeneous • same throughout, particles so tiny that cannot be seen, don’t settle out or scatter light • Examples: milk, salt water and cola –Heterogeneous • a mixture in which different materials can be easily distinguished • Suspension-visible particles settle-muddy water • Examples: Sand/water, Italian salad dressing, pizza and dry soups 5

Classification of Matter 6

Measuring Matter Volume of a liquid – Graduated cylinder- read from bottom of meniscus Volume of solid – Length X Width X Height Volume of Irregular Shaped Objects – Water Displacement Indirect Measuring – Large objects-take a core sample and use a formula – Small objects-weigh 100 and then divide weight by 100 to get one small objects weight 7

Phases & Properties of Matter What is the matter? 8

Phases of Matter Solids - definite shape and volume Atoms are held close together by strong bonds l Movement is slow l Crystalline Solids (crystals) - atoms are arranged in regular fashion • Ex. - ice, salt, diamonds l Amorphous Solids - atoms LACK a regular arrangement • Ex. - rock, glass, wax l 9

Phases of Matter - Continued Liquids - definite volume, but NO definite shape Bonds are weaker and atoms are spaced farther apart l They take the shape of container they are in l 10

Phases of Matter - Continued Gases - NO definite volume OR shape l Bonds are weakest and atoms far apart l Expand to fill the container they are in • Examples - air, oxygen, smoke 11

Phases of Matter - Continued Plasma • Gas like mixture of + and – charged particles l Movement very rapid l 99% of mass of our solar system l Examples: Sun, Stars and Lightning 12

Properties of Matter • Physical Properties are the characteristics of matter that can be changed without changing its composition – characteristics that are directly observable • Chemical Properties are the characteristics that determine how the composition of matter changes as a result of contact with other matter or the influence of energy 13

Extensive and Intensive Properties An extensive property of a material depends upon how much matter is is being considered. • mass • length • volume An intensive property of a material does not depend upon how much matter is is being considered. • density • temperature • color 1. 6

Some Physical Properties 15

Some Chemical Properties 16

Some Physical Properties of Iron • iron is a silvery solid at room temperature with a metallic taste and smooth texture • iron melts at 1538°C and boils at 4428°C • iron’s density is 7. 87 g/cm 3 • iron can be magnetized • iron conducts electricity, but not as well as most other common metals • iron’s ductility and thermal conductivity are about average for a metal • it requires 0. 45 J of heat energy to raise the temperature of one gram of iron by 1°C 17

Some Chemical Properties of Iron • iron is easily oxidized in moist air to form rust • when iron is added to hydrochloric acid, it produces a solution of ferric chloride and hydrogen gas • iron is more reactive than silver, but less reactive than magnesium 18

Changes in Matter • Physical Changes - changes in the properties of matter that do not effect its composition – Heating water • raises its temperature, but it is still water – Evaporating butane from a lighter – Dissolving sugar in water • even though the sugar seems to disappear, it can easily be separated back into sugar and water by evaporation 19

Changes in Matter • Chemical Changes involve a change in the properties of matter that change its composition – a Chemical Reaction – rusting is iron combining with oxygen to make iron(III) oxide – burning butane from a lighter changes it into carbon dioxide and water – silver combines with sulfur in the air to make tarnish 20

• Is it a Physical or Chemical Change? a physical change results in a different form of the same substance – the kinds of molecules don’t change • a chemical change results in one or more completely new substances – the new substances have different molecules than the original substances – you will observe different physical properties because the new substances have their own physical properties 21

Physical Properties of Matter • Viscosity – · · • Measure of the material’s resistance to flow • High-viscosity liquids take longer to flow • Example: Ketchup when comparing to water • Low-viscosity liquids flow easier • Example: Tomato Juice flows easier than ketchup • Temperature raising-viscosity decreases except in gases. 22

Physical Properties of Matter – Cont. • Elasticity – • Measure of ability to be stretched and then return to its original size. • Example: Rubber Bands, Elastic, and Playground Balls Question: Which ball would you rather play basketball? 23

Physical Properties of Matter – Cont. • Malleability – • Ability to be hammered into sheets • Example: Gold &Silver Coins, Aluminum Foil and Soda Cans 24

Physical Properties of Matter – Cont. • Brittleness – • measures a material’s tendency to shatter upon impact • Example: Sulfur, Calcium and Glass • Hardness – • Resistance to breaking or scratching • Example: diamonds 25

Physical Properties of Matter – Cont. • Luster – • shininess • Example: Gold, Silver, Mercury • Ductility – • ability to be pulled into wires • Example: Most metals (Copper, Silver) 26

Physical Properties of Matter – Cont. Tensile Strength • Measure of how much pulling, or tension, a material can withstand before breaking • Property of fibers, ropes, cables, girders • Du. Pont Kevlar-5 times tensile strength of steel 27

Physical Properties of Matter – Cont. • Density – • The amount of mass in a given volume • How tightly packed the atoms or molecules are in a substance • Formula to calculate density is: Density = Mass Volume • Units are expressed as: • g/m. L or g/L for liquids (remember the graduated cylinder) • g/cm 3 for solids 28

Density of a Fluid • Any matter that is able to flow • Liquids and gases • Density of a liquid might be different from the density of the same solid • Most materials are denser in solid phase than their liquid phase • Exception- Water-freezes with air spaces so it is less dense and floats. • Density of water is 1 g/cm 3 29

Physical Properties of Matter – Cont. • Buoyancy – • Upward force a fluid exerts on an object • Determines whether the object will sink or float • Example: Buoyancy of water keeping you afloat while swimming 30

Buoyancy force is LESS then object’s weight, object will SINK Buoyancy force is equal to the object’s weight, object will FLOAT Buoyancy force is MORE then object’s weight, object will FLOAT IN AIR 31