Chapter 1Chapter 1

Science SkillsScience Skills

Chemistry 1Chemistry 1

What is Science – 1.1What is Science – 1.1

T/F? Science consissts of T/F? Science consissts of unchanging body of known unchanging body of known facts.facts.

T/F? Scientific Laws can T/F? Scientific Laws can change.change.

T/F? Theories can change.T/F? Theories can change. How are science and How are science and

technology related?technology related?

Science From Curiosity 1.1Science From Curiosity 1.1

Led to use of fire, building of Led to use of fire, building of tools, and languagetools, and language

Science begins with curiosity Science begins with curiosity and often ends with discoveryand often ends with discovery Curisosity and scientific Curisosity and scientific

experimentexperiment

Science Improves Our Quality of Life 1.1

Advances in science have led to devices that make our lives easier and more pleasant. For example, the microwave oven makes it possible to prepare meals and snacks in minutes rather than hours.

1. Name five household devices that makeyour life easier or more pleasant.2. Go through your list and describe howeach device’s function was accomplishedbefore its invention.

Branches of Science 1.1Branches of Science 1.1 3 branches3 branches

1.1. Physical SciencePhysical Science ChemistryChemistry – study of the composition, – study of the composition,

structure, properties, and reactions of matterstructure, properties, and reactions of matter PhysicsPhysics – study of matter and energy and the – study of matter and energy and the

interactions between the 2interactions between the 2

2.2. Earth and Space ScienceEarth and Space Science GeologyGeology – study of the origin, history, and – study of the origin, history, and

structure of Earthstructure of Earth AstronomyAstronomy – study of the universe beyond – study of the universe beyond

Earth (sun, moon, planets, and stars)Earth (sun, moon, planets, and stars)

3.3. Life ScienceLife Science Biology –Biology – study of living things (physics, study of living things (physics,

chemistry, origin and behavior of living thingschemistry, origin and behavior of living things

OVERLAPING OVERLAPING

The Big Ideas of Physical The Big Ideas of Physical Science - 1.1Science - 1.1

Space and TimeSpace and Time Universe = very old AND Universe = very old AND BIGBIG 12.7 billion years old12.7 billion years old 700 million billion billion billion 700 million billion billion billion

meters in diameter = universemeters in diameter = universe 12,700,700 meters in diameter = 12,700,700 meters in diameter =

EarthEarth

The Big Ideas of Physical The Big Ideas of Physical Science Continued - 1.1Science Continued - 1.1

Matter and ChangeMatter and Change Small amt of universe is matterSmall amt of universe is matter Has volume and massHas volume and mass Normally liquid, solid, gasNormally liquid, solid, gas Made of atomsMade of atoms

Electrons, protons, and neutronsElectrons, protons, and neutrons

Forces and MotionForces and Motion Forces cause changes in motionForces cause changes in motion

The Big Ideas of Physical The Big Ideas of Physical Science Continued - 1.1Science Continued - 1.1

EnergyEnergy Kinetic energy – energy in motionKinetic energy – energy in motion Potential energy – objects moevd Potential energy – objects moevd

against a force against a force Matter absorbs and releases Matter absorbs and releases

energyenergy Can be transferredCan be transferred

Science and Your PerspectiveScience and Your Perspective

Science is both a process and a Science is both a process and a body of knowledgebody of knowledge

Science is always changingScience is always changing

Using a Scientific Approach Using a Scientific Approach 1.21.2

Design Your Own ExperimentSuppose that you want to conduct a test

to see which brand of cleanser produces the best results when cleaning a kitchen floor. Think about how you would conduct this test.

1. What materials would you need?2. What procedure would you follow?3. How would you determine whichcleanser produces the best results?

Scientific Method 1.2Scientific Method 1.2 Organized plan for gathering, organizing, Organized plan for gathering, organizing,

and communicating informationand communicating information Goal: solve a problem or better Goal: solve a problem or better

understand an observed eventunderstand an observed event1.1. Make observation – information that you Make observation – information that you

obtain thru your sensesobtain thru your senses2.2. Form Hypothesis – proposed answer to a Form Hypothesis – proposed answer to a

questionquestion3.3. Test Hypothesis – experimentTest Hypothesis – experiment

Manipulated variable – IV – causes a change Manipulated variable – IV – causes a change in something else – I CHANGEin something else – I CHANGE

Responding Variable – DV – variable that Responding Variable – DV – variable that changes b/c of IVchanges b/c of IV

Controlled experiment – one variable is Controlled experiment – one variable is changed at a timechanged at a time

4.4. Draw a conclusionDraw a conclusion If data doesn’t support hypothesis , scientist If data doesn’t support hypothesis , scientist

revises a hypothesis revises a hypothesis new test new test

Theory vs. Law – 1.2Theory vs. Law – 1.2 Theory - well-tested explanation Theory - well-tested explanation

for a set of observations or for a set of observations or experimental resultsexperimental results Never provedNever proved Stronger if the facts support themStronger if the facts support them May be revised or replaceMay be revised or replace

Law – summarizes patterns in Law – summarizes patterns in naturenature Does not explain observation Does not explain observation

(explanation is provided by theory)(explanation is provided by theory)

Models – 1.2Models – 1.2 Representation of an objectRepresentation of an object Makes things easier to understand Makes things easier to understand

May be too difficult to observeMay be too difficult to observe Physical ModelPhysical Model

Ex: how Earth rotates on its axisEx: how Earth rotates on its axis Computer modelsComputer models Mental model Mental model

Ex: comets are like giant snowball, Ex: comets are like giant snowball, mostly mad of icemostly mad of ice

Challenge models to find new dataChallenge models to find new data

1.3 Measurement1.3 Measurement Important in science and everyday Important in science and everyday

lifelife Scientific Notation – way of Scientific Notation – way of

expressing a value as the product expressing a value as the product of a number between 1 and 10 and of a number between 1 and 10 and a power of 10a power of 10 Use with very large or very small Use with very large or very small

numbersnumbers Numbers less than 1 have a negative Numbers less than 1 have a negative

exponentexponent Negative means move the decimal to the Negative means move the decimal to the

leftleft

1.3 Continued…1.3 Continued…Scientific NotationScientific Notation

Multiplying numbers in scientific Multiplying numbers in scientific notationnotation

1.1. Multiply number that appear before Multiply number that appear before the multiplication signsthe multiplication signs

2.2. Add the exponentsAdd the exponents Dividing numbers in scientific Dividing numbers in scientific

notationnotation1.1. Divide the numbers that appear before Divide the numbers that appear before

the exponential termthe exponential term

2.2. Subtract the exponentsSubtract the exponents Matt Skills problems page 15Matt Skills problems page 15

1.3 Continued…1.3 Continued…SI Units of MeasurementSI Units of Measurement

Number and unitNumber and unit International System of UnitsInternational System of Units Developed in France in 1791Developed in France in 1791 1 system of units, scientist can 1 system of units, scientist can

easily interpret another’s easily interpret another’s measurementmeasurement

Continued 1.3Continued 1.3Base UnitsBase Units

Base QuantityBase Quantity Base UnitBase Unit SymbolSymbol

LengthLength MeterMeter MM

Mass Mass KilogramKilogram KgKg

TimeTime SecondSecond SS

TemperatureTemperature KelvinKelvin KK

Amount of a Amount of a substancesubstance

MoleMole MolMol

Electric CurrentElectric Current AmpereAmpere AA

Luminous Luminous IntensityIntensity

CandelaCandela cdcd

Continued 1.3Continued 1.3Base UnitsBase Units

Length – straight-line distance Length – straight-line distance between 2 points between 2 points

Mass- quantity of matter in an Mass- quantity of matter in an objectobject

1.3 Continued1.3 ContinuedDerived UnitsDerived Units

QuantityQuantity UnitUnit SymbolSymbol

AreaArea Square meterSquare meter mm22

VolumeVolume Cubic meterCubic meter mm33

DensityDensity Kilograms per Kilograms per cubic metercubic meter

Kg/mKg/m33

PressurePressure Pascal Pascal (kg/m(kg/m..ss22))

PaPa

EnergyEnergy Joule Joule (kg(kg..mm22/m/m22))

JJ

FrequencyFrequency Hertz (1/s)Hertz (1/s) HzHz

Electric Electric chargecharge

Coulomb (ACoulomb (A..s)s) CC

1.3 Continued…1.3 Continued…Derived UnitsDerived Units

Combination of base unitsCombination of base units Volume – the amount of space Volume – the amount of space

taken up by an objecttaken up by an object Density – ratio of an object’s Density – ratio of an object’s

mass to its volumemass to its volume Density = mass/volumeDensity = mass/volume

1.3 Continued…1.3 Continued…Metric PrefixesMetric Prefixes

Kids Have Dropped Over Dead ConvertingMetrics Kilo Hecto Deca Origin deci Centi Mili Kg hg dag(Dg) g dg cg mg

Giga = 1 000 000 000 = G Mega = 1 000 000 = M Micro = .000 001 = u Nano = .000 000 001 = n Conversion Factor – ratio expressed in one unit

to another unit

1.3 Continued…1.3 Continued…Precision and AccuracyPrecision and Accuracy

dictionary definitions do not clearly make dictionary definitions do not clearly make the distinction as it is used in the sciencethe distinction as it is used in the science

Accurate - "capable of providing a correct Accurate - "capable of providing a correct reading or measurement." In physical reading or measurement." In physical science = 'correct'. A measurement is science = 'correct'. A measurement is accurate if it correctly reflects the size of accurate if it correctly reflects the size of the thing being measured.the thing being measured.

Precise - "exact, as in performance, Precise - "exact, as in performance, execution, or amount. "In physical science execution, or amount. "In physical science = "repeatable, reliable, getting the same = "repeatable, reliable, getting the same measurement each time."measurement each time."

We can never make a perfect measurement. We can never make a perfect measurement. The best we can do is to come as close as The best we can do is to come as close as possible within the limitations of the possible within the limitations of the measuring instruments.measuring instruments.

1.3 Continued…1.3 Continued…Significant FiguresSignificant Figures

All the digits that are known in a All the digits that are known in a measurement, plus the last digit measurement, plus the last digit that is estimatedthat is estimated

The fewer the sig figs, the less The fewer the sig figs, the less preciseprecise

Measuring Temperature 1.3Measuring Temperature 1.3

Instrument that measures Instrument that measures temperature, or how hot an temperature, or how hot an object isobject is

Celsius = (5/9)(F – 32)Celsius = (5/9)(F – 32) Fahrenheit = (9/5)(C) + 32Fahrenheit = (9/5)(C) + 32 Kelvin = C + 273Kelvin = C + 273 Read Page 21Read Page 21

Presenting Scientific Data 1.4Presenting Scientific Data 1.4 Organizing Data (makes easier to interpret)Organizing Data (makes easier to interpret)

Data TablesData Tables Relates 2 variables (the IV and DV)Relates 2 variables (the IV and DV) Figure 20, page 22Figure 20, page 22

Line GraphsLine Graphs Useful for showing changes that occur in Useful for showing changes that occur in

related variablesrelated variables IV = x-axis – horizontalIV = x-axis – horizontal DV= y-axis – verticalDV= y-axis – vertical

Line Graphs Continued – 1.4Line Graphs Continued – 1.4 Slope (steepness) = Rise/RunSlope (steepness) = Rise/Run

Change in y/Change in xChange in y/Change in x (y(y22-y-y11)/(x)/(x22-x-x11)) ΔΔy/y/ΔΔxx

Direct Proportion – one increases, the Direct Proportion – one increases, the other increasesother increases Ex: double volume = double massEx: double volume = double mass

Triple volume = triple massTriple volume = triple mass Inverse Proportion – one increases, the Inverse Proportion – one increases, the

other decreasesother decreases Altitude increases, temperature Altitude increases, temperature

decreasesdecreases

Bar/Circle Graphs – 1.4Bar/Circle Graphs – 1.4 BarBar

Used o compare a set of measurement, Used o compare a set of measurement, amounts, or changesamounts, or changes

Easy to see how the data compares to Easy to see how the data compares to anotheranother

CircleCircle Shows how something relates to the Shows how something relates to the

wholewhole

Communicating Data 1.4Communicating Data 1.4 Journals, conferences, email, Journals, conferences, email,

web, conversations, science web, conversations, science fairsfairs

Peer Review – process when Peer Review – process when scientist examines other scientist examines other scientists’ workscientists’ work Accurate, honest, feedback,Accurate, honest, feedback,

Crucial part of any investigationCrucial part of any investigation