Chapter 15 Forms of matter Pages

Chemical Changes How to know if a chemical change took place? New substances are formed. Energy is given off

Matter can be Pure Substance -elements or compounds -hard to break apart -well defined composition Mixture -easy to separate into the components through common physical properties Composition variable

Element vs. Compound Elements – one type of atom. Compounds – two or more atoms chemically combined.

More about mixtures…….. Heterogeneous Homogeneous

More mixture terminology Solutions Colloids Suspensions

Properties of matter Physical properties – Describe what something looks like. color Metal? Conductor? Magnetic? State? Chemical Properties – Describe how matter will act Flammable Reactive Corrosive Toxic

T/F All metals are magnetic All metals are conductors

Underline chemical and circle the physical properties.. Methane is a colorless, odorless gas at room temperature, It is less dense than air and is highly flammable.

Chemical and Physical Changes Physical Changes Any change in density, color, shape.. No new substances are made. Chemical Changes New substances are formed. Often energy changes occur

samples Cork Rubber Wood Zinc Copper Aluminum Tin Iron plastic

What physical properties do all metals share?????

ATB Was the demonstrations a physical or chemical change? Why?

ATB How would this be classified?

Mr. Frink obtained a beaker of a clear, odorless liquid. Upon further investigation he determined it to be an inflammable substance, to test this he ignited it. It burned vigorously producing carbon dioxide and water in the process.

Lab – Separating mixtures Purpose: To separate mixtures into their components. Hypothesis: Will we be able to use physical properties to separate mixtures???? Materials and Methods Day 1: chromotography Test tube, mixture, chromatography paper Day 2: magnetism, filtration, evaporation Mixture, magnet, googles, apron, filter paper, funnel, tin tray, stand, plastic tray

Observations Day 1: Chromatography Day 2/3 Magnetism, filtration, boiling

Conclusion 1. Explain why we started with mixtures in both labs. 2. What properties did we use to separate the mixtures?

Vocab Card List Substance Element Compound Heterogeneous Homgeneous Colloid Tyndall effect Suspension Fog Physical property Chemical property Physical change Chemical change Distillation L.O.C.O.M. mixture

Methods 1 tray of mixture Run magnet through it Add 20 ml of water Filter it Let the water evaporate

Lab – Heat conductivity of metals Purpose: The purpose is to measure how fast various metals conduct heat energy. Materials and Methods Goggles, Bunsen Burner, timer, wax, conductivity tester,

Data…. Table of metal vs. time to melt Bar graph of metal vs. time to melt

Conclusion Is this lab a measurement of physical or chemical properties? Explain why. How does thermal conductivity relate to The Kinetic Theory of Matter?

Mixtures Two or more substances that are easily separated by physical means into their components.

Two categories of mixtures.. Heterogeneous- Components are easily distinguished suspensions Homogenous- Components are blended evenly

Types of mixtures Solutions Colloids suspensions

ATB- A paragraph in your notebook Based on the results of the chromatography lab, was the food coloring an element, compound or mixture? Why

Lab – Separating a mixture. Purpose: The purpose is to separate a mixture into its’ components using physical properties. Hypothesis: How many components will compose the mixture?

Materials and Methods Goggles and apron Magnet Mixture sample Funnel and filter paper Tin tray Spatula stand

Methods Step 1: separate using magnetism Step 2: filtration Step 3: evaporation

Observations What were the components of the mixture, describe how we separated them.

Conclusion Was this a heterogeneous or homogenous mixture? Explain why. What physical properties did we use to separate the mixture?

LOCOM The law of conservation of mass In a “normal” chemical reaction no mass is created or destroyed. This is a reaction that is not "normal"

LOCOM Lab Purpose: The purpose is to prove LOCOM by burning steel wool. Hypothesis: Will we violate the “law”. Materials and Methods Data: Mass before =____________g Mass after =___________g

GroupBefore massAfter mass

Conclusion Why did the steel wool gain mass? Did we violate the “law”? What is the equation for what happened? What were the chemical and physical changes you saw during the experiment?

Test review – chapter 15 Pure substances Element Na, Cl H O Compounds NaCl H 2 O Mixtures Heterogeneous Uneven, Colloids suspensions Homogeneous Evenly blended solutions

Separating mixtures Use physical properties Magnetism Boiling point (distallation) Filtration

Properties of Matter Physical Properties State, color, density, appearance, texture Chemical Properties Reactivity, flammability, corrosive toxic

Physical Changes Nothing new made Chemical Changes New substances made, energy is produced or absorbed

LOCOM Mass is conserved H 2 + O 2 -  H 2 O