Physical Science Chapter 2 Notes The Properties of Matter

Chapter 2 Overview Section 1: What is Matter? –Matter has Volume and Mass –Difference between Mass and Weight –Mass is a measure of Inertia Section 2: Describing Matter –Physical and Chemical Properties –Physical and Chemical Changes

Section 1: What is Matter? Matter = anything that has Volume & Mass Volume is the amount of space taken up No 2 objects can occupy the same space at the same time. Volume of a Liquid - Read at the Meniscus Volume of Solid –Measure directly if rectangular sides –If irregular sides, then can use displacement –Relationship between mL and cm 3

More on Matter Math Break p. 38 Volume of Air –The volume of air is simply the volume of the container it is in Matter has Mass Mass is the amount of matter in a given substance Mass does not change unless you remove or add more matter to the object (p. 39 )

Examples of Matter

Where does the mass of a child come from as she grows? Does she have mass and volume? Does her volume and mass increases as she grows? Food adds both space into matter

Mass and Weight Differences Mass is a measure of the amount of matter in an object- balance beam Weight is the measure of the gravitational force on an object. Depends on mass and distance** p. 39 Figure 6. Weight measured with a spring scale

MASS WEIGHT Amount of Matter Always constant Measured with Balance Expressed in kg, g, mg A Measure of the Gravitational Force Varies depends on distance and mass Measured with Spring Scale Expressed in Newtons

Mass and Weight are Related Weight is pretty much constant on Earth because gravity is constant on the surface of the Earth Force = Mass times Acceleration

Mass is a Measure of Inertia Inertia is the tendency of all objects to resist change in motion. Light objects easy to move Heavy objects not so easy to move P. 152: Momentum is a property of a moving object that depends on the objects mass and velocity. Faster and heavier, harder to stop.

Measuring Matter Experimenting skills worksheet Read #1 How could this be done?

Measuring matter Look at the charts on Tools of the trade. Fill in the type of tool that you would use to measure each object or the measurement for that tool in the chart.

Measuring matter In a graduated cylinder or beaker, most liquids form a meniscus. This looks like an arc or the liquid curves up at the edges like a smile. Now do the problems…

Measuring Matter Uncertainty in measurements…. This is possible. This can happen for many reasons. Your lab equipment has error. Yes, there is human error. You measured wrong…Read the data wrong…Mixed the wrong ingredients or chemicals…Did not accurately read at the meniscus…etc. Your data you collected has to be as accurate as possible, so many times you have to allow for error or repeat your experiment again. Accuracy is the foundation of science. If we were not accurate we could blow ourselves up….. Lets read the scenario in uncertainty…

Section 2 Describing Matter

Matter can be described using different properties. Describe these objects. Matter is described using Physical and Chemical Properties

Physical Property Physical Properties can be observed and measured without changing the ID object Examples of Physical Properties (p. 44) –Thermal Conductivity (transfer of heat) –State (solid, liquid, gas) –Malleability (ability to flatten) –Ductility (ability to be pulled into wires) –Solubility (ability to dissolve) –Density (mass per unit volume)

Density D=M/V Also can be described as amount of matter per given volume Can use to identify substances (like gold vs. pyrite) Math time

Chemical Property Ability to change into a new substance Examples of chemical Properties –flammability –Non-flammability –React with Oxygen –React with acid or base –React with water

Physical vs. Chemical Changes Physical changes are changes that affects the physical properties of a substance –Example. Ice to Water, breaking a piece of chalk, crumpling paper, sugar in lemonade Chemical changes occur when one or more substances are changed into entirely new substances. –Examples. Burning paper, mixing acid with chalk, oxidizing metal, souring of milk

Clues to Chemical Changes Physical changes can be reversed. (ice-water) Chemical changes cannot be reversed. Clues for chemical changes include: –color changes –visible reaction –smells –heat/light –gas bubbles