T HE M ATERIAL W ORLD Properties of Matter. P ROPERTIES There is material all around us. This could...

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Transcript of T HE M ATERIAL W ORLD Properties of Matter. P ROPERTIES There is material all around us. This could...

THE MATERIAL

WORLDProperties of Matter

PROPERTIESThere is material all around us. This could be natural or synthetic (manmade)

These materials are distinguished from one another by their properties.

It is these properties that will determine how different materials will react with one another.

For example: Oil and water or salt and water.

CHARACTERISTIC PROPERTIESProperty: information used to describe a substance.

There are physical properties; properties we can observe without changing the material.

Chemical properties; describes how substances react with one another.

Characteristic properties can be both physical or chemical.

These properties are:1.Color2.Texture3.Taste4.Shape5.State (gas, liquid, solid)6.Ductility & Malleability7.Melting and boiling point8.Density9.Use or need

MASS AND VOLUMETo measure the volume of a liquid

simply read the measurement off of a graduated cylinder.

NOTE: be sure to read the bottom of the meniscus.

Volume is the amount of space taken up by an object

Volume of a cube:V= s x s x s

(All sides of a Cube are equal)

S

S

S

Volume of a rectangular prism:

V= l x w x h

w

h

l

To measure the volume of an irregular shaped object, ex: rock, use the water displacement method.

Water displacement method:1.Fill a graduated cylinder with a

known quantity of liquid.2.Place the object in the cylinder 3.Follow this formula

V= Vf (water with object) – Vi (just water)

Mass is very easy to calculate.Simply place the object on a scale or

balance.Use of the triple beam balance will

be explained in the lab.

EXAMPLE PROBLEMS1. Volume of a cube with a side of

3.5 cm.2. Volume of a rectangular prism

with a length of 7cm, width of 4cm, and height of 1.5cm

3. Volume of a rock that raised the water in a graduated cylinder(GC) 4ml from the original 15ml.

DENSITYMass and volume are not considered

characteristic properties.This is due to the fact that many

objects could have the same mass and volume.

In these cases one would have to calculate the density of the objects.

Density: measures the amount of matter (particles or stuff) in a substance.

To calculate the density of an object one must know the mass and the volume.

Density is calculated using the following formula:

D = m/v

The formula reads density is equal to mass divided by volume.

The units for density are g/ml

EXAMPLE PROBLEMS1. Density of an object with a mass

of 10g and a volume of 2ml.2. Density of a substance with a

mass of 100g and a volume of 20ml.

3. Density of a cube with a mass of 40g and a side of 2cm.

4. Density of a bracelet with a mass of 12g and raised the water in a GC 2ml from 20ml.

TEMPERATURETemperature: is the measurement of the degree of agitation of the particles that make up a substance.

This means when a substance is heated the particles begin to move around.

This movement causes heat.The faster the particles move the higher

the temperature.A substance cools down when the

particles are less agitated.

STATES OF MATTERA state is the form in which matter

can be found.There are three states;1.Solid: ice, wood, salt, sugar2.Liquid: water, mercury, vinegar3.Gas: steam, methane, propaneSome substances can be found in all

three states. Ex: water

ACIDITY AND ALKALINITYpH is the measure of how acidic or

how basic (alkalinity) a solution is.pH scale measures solutions (liquids)The pH scale has a range of 0-14.If a solution falls into the 0-7 range it

is an acid, 7-14 it is a base (alkaline).0 = battery acid, 14 = drain cleanerIf a solution is 7 it is neutral ex: pure

water.

CHANGES IN MATTERThere are two types of changes.Matter: anything that has mass and

occupies space. Stuff that makes up a substance

1.Physical changes: occurs when the appearance of the substance is changed only.

2.Chemical changes: when two substances interact to create a new substance.

PHYSICAL CHANGES All of a substance’s chemical

makeup stays the same.Examples:1.A broken dish2.Paper torn in two3.Broken mirror4.Ice melting5.Ground coffee6.Shredding cheese

CHEMICAL CHANGESThere are four simple signs that a

substance is undergoing a chemical change.

1.Change in color: metal rusting, fruit going bad, etc.

2.Formation of a gas (you will see bubbles/foam): baking soda and vinegar, antacid and water.

3) Formation of a precipitate: creates a solid at the bottom of the mixture that does not dissolve.

Example: Too much chocolate powder in milk.

4) Energy change: a substance will give off or release energy. This usually results in a temperature change.

Example: salt and ice, ice packs.

CONSERVATION OF MATTERLaw of Conservation of matter states:The quantity of matter or total mass of a closed system will remain constant regardless of the process that takes place within the system.

This includes chemical reactions and physical changes.

Example: if ice melts in a sealed container it will have the same mass.

MIXTURESA mixture is a substance that contains more than one type of particle.

For example: salt and water, vinegar and baking soda.

Homogeneous mixtures: substances whose parts are completely mixed together (fully dissolved)

Examples: salt and water, tea, coffee, lemonade, ice tea

Heterogeneous mixtures: substances whose particles are not fully mixed together (not dissolved)

Examples: water and sand, oil and water.

SOLUTIONSA solution is a homogeneous mixture

(particles are fully dissolved).A solution has two parts.1.Solute: substance being dissolved

(ex: salt)2.Solvent: substance doing the

dissolving. (ex: water)Solutions can be saturated solvent

can not dissolve any more solute

A solution becomes saturated when too much solute poured into a solvent.

Solutions can also be unsaturated solvent can dissolve more solute.

1.What are some examples of heterogeneous mixtures?

2.What are some examples of homogeneous mixtures?

3.Provide some examples of saturated and unsaturated solutions.

SEPARATION OF MIXTURESThe separation of different mixtures

is not always an easy task.For heterogeneous mixtures this

process is quite simple.Simply remove the solid or the

lighter (less dense) substance.For example: oil and water or sand

and water.

For homogeneous mixtures the process is slightly more complicated.

There are five techniques that one could use to separate mixtures.

1) Filtration: a process that separates the parts of a mixture by retaining large particles and letting smaller one pass through.

Example: making coffee, filtering cooking oil, a screen over a window.

2) Hand- pressing: process that extracts a liquid from a mixture using manual force (by hand).

Example: squeezing juice from a fruit or vegetable, making oil.

3) Sedimentation: process that consists of allowing solid particles to settle at the bottom of a motionless mixture.

Example: paint sitting on a shelf, salad dressing

4) Drying: process that uses evaporation by heat to remove water from a mixture.

Example: Removing salt from water, removing alcohol from wine.

5) Grinding: process that reduces a solid into very small particles by either crushing or cutting.

Example: making wine, making jam

ELEMENTSDifferent objects are composed of

different substances. Characteristic properties allow us to

tell different substances apart.Substances are made up of elements .Elements are the basic units (smallest

parts) that compose all matter.These elements could be solids,

liquids and gas.

THE PERIODIC TABLEIn 1865 a Russian chemist, Dimitri

Mendeleev created a way of classifying elements.

He would classify these elements in a table according to their properties.

The first periodic table created in 1869 contained only 63 elements.

Today there are over one hundred elements in the table.

The Periodic table has elements in individual squares arranged in columns and rows.

Each square contains the element symbol, name and number.

The numbers increase from left to right.

The first row contains two elements only.

Rows 2 and 3 contain six. The table also contains the atomic

weight of each of these elements.

ATOMS An atom is the smallest unit of

matter.All known atoms are classified in the

periodic table.Most periodic tables will provide

several pieces of information.The most important is the chemical

symbol. Ex: Hydrogen = HThese symbols are universal. Ex: In

Germany Hydrogen= Wasserstoff = H

All elements are pure substances.Therefore, the periodic table shows

all known elements which are pure substances.1.H=hydrogen2.He=helium3.Li=lithium4.Be=beryllium5.B=boron6.C=carbon 7.N=nitrogen8.O=oxygen9.F=fluorine10.Ne=neon

11.Na=sodium12.Mg=magnesium13.Al=aluminum14.Si=silicon15.P=phosphorous16.S=sulfur17.Cl=chlorine18.Ar=argon19.K=potassium20.Ca=calcium

All Atoms have two major parts the nucleus and the electrons.

The electrons revolve around the nucleus, like planets revolve around the sun.

Inside each nucleus there are protons and neutrons.

MOLECULESElements are pure, therefore they are

not mixed with any other substances.Atoms are the smallest part of an

element.When two or more elements get

mixed together it becomes compound (mixture).

A molecule is the smallest part of a compound. Ex: Water= H2O, Salt=NaCl

READING COMPOUNDSAs mentioned above the smallest

part of an element is an atom.Since an element is a pure

substance it will only have one part (no mixture).

A compound is a mixture of two or more elements.

Therefore, a compound has more then one part.

The smallest part of a compound is a molecule.

A molecule is made up of two or more atoms.

When reading a compound you will be able to see how many of each atom is present.

For example: H2O has 2 Hydrogen atoms and 1 Oxygen.

To read this you must look at the number directly after the atom.

If there is no number it is understood that it is a 1.

Example: C2H4 This molecule has 2 Carbon atoms and 4 Hydrogen atoms.

Complete the following examples:1.H2SO4

2.CH4

3.NaOH4.BeF2O6

5.Mg2He3

6.Ca(OH2)3

If there is brackets, you must multiply all of the numbers on the inside of the brackets by the number on the outside.

Ex: Ca(OH2)3 Has 1 Calcium, 3 Oxygen, and 6 Hydrogen.

1.H3(Be3F2)4

2.Na(O2Ne2)2

3.He6(C2)3

4.O(H3F)2

5.N5(H2F3)4

DRAWING ATOMS AND MOLECULES The first step you must

determine how many of each atom is present.

Ex: H2O has 2Hydrogen and 1 Oxygen

Next you have to draw circles that correspond to each of the atoms identified. Be sure to label.

MOTIONMotion: is the change of position or

location over a certain length of time.Basically motion is the movement of

an object.Motion is the result of an applied

force.In Physics motion is usually

measured in terms of velocity and speed.

For an object to move there must be a force that is applied to it.

No object can move on it’s own.An object that is not moving is said to

be at rest.

TYPES OF MOTIONThere are three types of motion.1)Translational MotionThis is the when an object moves in a

straight line. Ex: Car, bike2) Rotational MotionThis is when an object moves in a circle.

Ex: Merry-go-round, wheel3) Spiral MotionThis is when an object moves in spiral.

Ex: Cork screw, screw

FORCEIn Physics a force is any action that

allows an object to move.Ex: pushing a shopping cart A force can also change the speed or

direction (trajectory) of an object that is already in motion.

Ex: curling, pool, bocceFinally a force can deform (change

the shape) of an object.Ex: stretching an elastic, leggings

TYPES OF FORCEThere are five types of force1) TensionThis force will stretch an objectEx: bow and arrow, elastic

2) CompressionThis force will compress (squeeze) an

object.Ex: squeezing a sponge, crushing a

can

3) Torsion This force will twist an objectEx: opening a jar, twisting your ankle.

4) FlexionThis is the force that will bend an

object.Ex: your spine, pole vault

5) ShearingThis is the force that will tear an

object.Ex: tearing a piece of paper,

earthquake

EFFECTS OF A FORCEAs mentioned above an object needs

a force to move.No object will move on its own.Therefore, the effects of a force is

motion.Even the human body is a complex

system of forces.In one movement the human body

can experience all five forces.

MECHANISMS THAT TRANSMIT MOTION

Motion can be transmitted to other components in a system.

A mechanism that transmits motion is will transfer motion of the same type to another component in a system.

In many systems oil and water are used as these mechanisms.

Ex: Hydraulics and hydro dams

Other components can be used to transfer motion.

Components like; gears, pulleys, belts, and chains all work together to transfer motion.

Describe how motion is transmitted in a bicycle

1. Force applied by the rider’s legs. Which causes the pedals to move (translational motion)

2. The arms of the pedals move in a circle (rotational motion)

3. The chain move backwards (translational motion) towards the back gears.

4. The back gear rotates which is attached to the rear wheel.

5. This allows the bicycle to move forward

SIMPLE MACHINESA simple machine is a mechanical

device that will change the direction of a force.

A simple machine uses one type of force to move an object.

There are 6 classical simple machines; lever, pulley, wheel & axle, inclined plane, wedge, screw

Provide one example of how each would be used

1. Lever: Hammer, letter opener, car jack

2. Pulley: clothes line, elevator3. Wheel & Axle: Car, bike4. Wedge: Axe, chisel5. Inclined plane: ramp, see-saw6. Screw: screw, cork screw

MECHANISMS THAT BRING ABOUT A CHANGE IN MOTION

Any object that is in motion can have its speed and direction changed.

This change would occur if another force is applied to this object.

An object being squeezed then stretched. Ex: dough

Ex: A ball bouncing off a wall Ex: Car crash.