T HE M ATERIAL W ORLD Properties of Matter

P ROPERTIES There 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.

C HARACTERISTIC P ROPERTIES Property: 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. Color 2. Texture 3. Taste 4. Shape 5. State (gas, liquid, solid) 6. Ductility & Malleability 7. Melting and boiling point 8. Density 9. Use or need

M ASS AND V OLUME To 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= V f (water with object) – V i (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.

E XAMPLE P ROBLEMS 1. 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.

D ENSITY Mass 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

E XAMPLE PROBLEMS 1. 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.

T EMPERATURE Temperature: 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.

S TATES OF M ATTER A state is the form in which matter can be found. There are three states; 1. Solid: ice, wood, salt, sugar 2. Liquid: water, mercury, vinegar 3. Gas: steam, methane, propane Some substances can be found in all three states. Ex: water

A CIDITY AND A LKALINITY pH 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 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 cleaner If a solution is 7 it is neutral ex: pure water.

C HANGES IN M ATTER There 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.

P HYSICAL C HANGES All of a substance’s chemical makeup stays the same. Examples: 1. A broken dish 2. Paper torn in two 3. Broken mirror 4. Ice melting 5. Ground coffee 6. Shredding cheese

C HEMICAL C HANGES There 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.

C ONSERVATION OF M ATTER Law 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.

M IXTURES A 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.

S OLUTIONS A 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.

S EPARATION OF M IXTURES The 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

E LEMENTS Different 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.

T HE P ERIODIC T ABLE In 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.

A TOMS 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 = H These 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=hydrogen 2.He=helium 3.Li=lithium 4.Be=beryllium 5.B=boron 6.C=carbon 7.N=nitrogen 8.O=oxygen 9.F=fluorine 10.Ne=neon 11.Na=sodium 12.Mg=magnesium 13.Al=aluminum 14.Si=silicon 15.P=phosphorous 16.S=sulfur 17.Cl=chlorine 18.Ar=argon 19.K=potassium 20.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.

M OLECULES Elements 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= H 2 O, Salt=NaCl

R EADING C OMPOUNDS As 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: H 2 O 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: C 2 H 4 This molecule has 2 Carbon atoms and 4 Hydrogen atoms. Complete the following examples: 1. H 2 SO 4 2. CH 4 3. NaOH 4. BeF 2 O 6 5. Mg 2 He 3 6. Ca(OH 2 ) 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(OH 2 ) 3 Has 1 Calcium, 3 Oxygen, and 6 Hydrogen. 1. H 3 (Be 3 F 2 ) 4 2. Na(O 2 Ne 2 ) 2 3. He 6 (C 2 ) 3 4. O(H 3 F) 2 5. N 5 (H 2 F 3 ) 4

D RAWING A TOMS AND M OLECULES The first step you must determine how many of each atom is present. Ex: H 2 O has 2Hydrogen and 1 Oxygen Next you have to draw circles that correspond to each of the atoms identified. Be sure to label.

M OTION Motion: 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.

T YPES OF M OTION There are three types of motion. 1)Translational Motion This is the when an object moves in a straight line. Ex: Car, bike 2) Rotational Motion This is when an object moves in a circle. Ex: Merry-go-round, wheel 3) Spiral Motion This is when an object moves in spiral. Ex: Cork screw, screw

F ORCE In 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, bocce Finally a force can deform (change the shape) of an object. Ex: stretching an elastic, leggings

T YPES OF FORCE There are five types of force 1) Tension This force will stretch an object Ex: bow and arrow, elastic

2) Compression This force will compress (squeeze) an object. Ex: squeezing a sponge, crushing a can

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

4) Flexion This is the force that will bend an object. Ex: your spine, pole vault

5) Shearing This is the force that will tear an object. Ex: tearing a piece of paper, earthquake

E FFECTS OF A F ORCE As 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.

M ECHANISMS THAT TRANSMIT M OTION 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

S IMPLE M ACHINES A 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, elevator 3. Wheel & Axle: Car, bike 4. Wedge: Axe, chisel 5. Inclined plane: ramp, see-saw 6. Screw: screw, cork screw

M ECHANISMS THAT BRING ABOUT A CHANGE IN M OTION 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.