Presentation on theme: "Of what is the Universe made?"— Presentation transcript:
1Of what is the Universe made? Today we will begin by examining this question. Please stress that as in all things, the first thing we must understand is the specialized vocabulary – the nomenclature – of that field. We also must understand the organizational structure of the field – how the field is organized and classification schemes used. Next slide.
2Insert new hubble photos to start the inquiry Ask: As you look at the vast universe shown in these recent photos, what do you see? What are these things made of?
3E=MC2 The Universe is Made of MatterEnergyNothingness -vacuumOtherMatter and Energy are really the same thing!Say, this is what scientists see as the things that make up the universe. Someone will always ask what the other is. Other includes dark matter and dark energy, which are thought to comprise most of what the universe is mad of, but we have yet to really figure out what these things are or if they are anything tangible. I always tell them that if they want to know about these things, they need to study hard and become an astrophysicist. Then maybe they will be able to figure it out.The law of conservation of matter and energy states that the all of the matter and energy that was in the universe at the beginning is still here. It never changes, but the energy may be converted to matter and matter into energy. Energy = Matter x C squared. C is the speed of light. Thus, you can convert matter to energy and energy to matter.When satisfied, Next SlideAs an aside, the massive, multi-billion dollar accelerator at the CERN (Centre European (for) Recherche Nuclear) on the French/Swill border, will attempt to cause the conversion of 100% of small particles of matter into pure energy some time soon. This would be a good research topic for GT students.E=MC2
4In this Hubble Photograph, you can see the matter and evidence of energy. What you also see, or think you see, is large amounts of nothingness. The vacuum of space. But what about “the other?”The other materials, dark matter and dark energy are only theoretical constructs and there is little tangible evidence to show they exist. Their existence is based on the discrepancy between the calculated mass of the universe (don’t ask) and the observed mass. The theory suggests that the discrepancy is accounted for by the existence of undetectable mass in the form of dark matter and its corollary dark energy. I don’t understand it, but that is what they say – they being the likes of Stephen Hawking and other egg head astrophysicists.
5Let us start with Matter. Sadly, in fifth grade we only Study Matter and Energy. We must ignore “other” until college.We leave study of “other” for colleges.Let us start with Matter.
6Matter What is it? Why is it important? KWL these two questions as a starting assessment of what the students know. Listen carfully as many misconceptions exist in this area of science.When satisfied, next slide.
7The official definition of matter? Definition: anything that has mass and occupies space (has volume.)Synonyms of “Matter” : material, stuff, substanceMatter is really anything that takes up space, but that will always be something that has mass so for practical purposes this definition is useful. Have student take notes from this point on if you want. It is good note taking practice. Next Slide
8So most of the things around us are matter Solicit more examples of matter from students and discuss why they are or are not matter. When you have enough, next slide.
10What are some things that are not matter? Thoughts, ideas, feelings, wordsSome smart kid might note that these things are forms of energy – neural impulses and sound waves- so could be converted to matter via e=mc2
11Let’s review today's discussion HOMEWORK: Read pages 306 – 320 in the text book and answer the questions on page 319This is the homework for this first day. Lesson ends here if you wish.THE RED BALL INDICATES SUGGESTED STOPPING POINTYou may also wish to use the Matter Pearson mini-books on matter (different reading levels available) as in class filler or as evening 30 minute reading material. May wish to use these as tool to teach annotation as a technique.
12Of what is Matter made?Solicit ideas discuss and then when ready proceed.Jane: don’t be nervous here, many of the slides are just to be read to the kids and don’t need a lot of explanation.
14Matter is made of small particles called ATOMS Fyi, but don’t tell kids this at this point: Atoms are said to derive from the thoughts of Greek philosopher Democritus. Legend has it that he was eating an apple and started to think that if he cut the apple, then cut it in half again, and again, and again, he would eventually get to the basic piece – the basic piece of apple beyond which you could not cut. He named this the Atom. Atom in Greek means: not (the prefix “a”) and cutable (root word, tomos, to cut.)
15Atoms are so small they can not be seen even with powerful microscopes
16A grain of salt is made of about 12,000,000,000,000,000,000 atoms
17Atoms were first named by an ancient Greek philosopher named Democritus And this is what people thought from BC until the late 1800s. More than 2000 years.
18He called it an “a tom” because in Greek it means “that which can’t be cut.” We still call this smallest piece an ATOMBut he thought of the atom as a kind of marble – a smooth round ball of whatever.Note that in the apple story, he thought there was a basic piece of apple. There is, but it is a MOLECULE, not an atom. Atoms joined together by bonds create molecules. Apples are made of many different molecules. The atom is, as we will see, the smallest particle of an Element.
19Close, But No Cigar He wasn’t completely w wrong, he was partly wrong! Tell the kids, We now know atoms are the smallest parts of something called an “element,” but they can be broken down into much smaller particles.
20Atoms have two basic parts A nucleus or center andelectron shellsOf course atoms consist of electrons, protons, and neutrons (sometimes) but these are organized into these two parts.
21The nucleus may be small or large PPNPNPPNNNPPNNNPNPNPNNPPThese particles are held together by a very powerful and little understood (especially by me) force creatively called the strong force. (As opposed to the weak nuclear force, which also has a role in holding the nucleus together.) It is billions, if not trillions, of times more powerful than gravity and is so strong that it makes the second strongest force (I think it is second) electromagnetism seem weak. This is important when we talk about atomic charge. All these positively charge protons should be blown apart by electromagnetic force. After all they all have positive charge. They stay together due to the overwhelming strong force.Nuclei are made of small particles called Protons and Neutrons
22The electron shells are in an area around the nucleus You can think of it as an orbit.Electron shells.This is the second major part of the Atom. The nucleus is the center, analogous to the sun, the electron shells is like the planets in orbit. Shells are technical and High School level, but if you have the kids think of the electron shells as different layers of orbits around the nucleus, it will work for now. Just be sure the kids understand that the “orbit” is not a nice neat circle, it is a wild, irregular, revolution around the nucleus.Good GT research topic.Nucleus
23So, unlike Democritus, we now know that atoms can be cut into smaller and smaller pieces themselves The parts of ATOMS areThe PROTON, which has a positive electrical chargeThe ELECTRON, which has a negative chargeAnd the NEUTRON which has no charge.Pro --- positiveNeutron --- neutral or no chargeElectron I can’t think of anything to help remember – just memorize it is negative.
24The Neutron (s) and Proton(s) make up the NUCLEUS or center of the atom Hydrogen, the most basic type of atom has no neutrons. All others do. The neutrons are thought to contribute the strong force and can be thought of a like glue that holds large nuclei together.
25The electrons “orbit the nucleus” of the atom Be careful to disabuse the students of the idea that electrons orbit the nucleus in a well defined, discrete, orbits. They orbit in a very disorganized and wild electron “cloud” in which the electrons move in nearly random patterns so they are not like planetary orbit except in a very general sense.
26Here is where Democritus was right. Once you cut the atom of something it is no longer the thing you started with.If you started with Gold, once you break the Gold atomit is no longer Gold!This is a critical understanding. Once you break an elemental atom, it is not that element. Likewise, the minute you break a molecule, you no longer have the compound that you started with.
27Atoms look something like this They have a Nucleus (center)SUGGESTED ENDING POINT FOR DAY TWO.Homework: Students will read page in their textbook about the properties of matter - mass, volume, and weight. Complete workbook pg. 5 & 11Note that this is not to scale. That misconception like all other ingrained at this age, last a long time and are very hard to get rid of. In fact, if you were to make an atom to scale so the proton was basket ball sized and you put it in the center of reliant stadium, the electrons would be peas “orbiting” in the parking lot. Most of the atom is made of nothing at all. It is mostly space.And little things that “orbit” the nucleus are the electrons
28Properties of Matter A property is like a characteristic ~~ something that describes something else
29When we talk about Matter There are three really important propertiestwo important propertiesanda bunch that are not as important, but still useful in classifying and identifying matter.
30Really Important Properties Volume– How Much Space It Takes upMass– How Much Stuff Is in the ThingAsk if students can explain. Give examples of things with great mass and ones with less mass. IT IS VERY IMPORTANT NOT TO SUGGEST THAT MASS AND VOLUME ARE RELATED. THEY ARE NOT. SOME OBJECT LIKE A LEAD WEIGHT ARE SMALL BUT HAVE GREAT MASS, THE MASS IS SQUISHED INTO A SMALLER SPACE. A SMALL LEAD SINKER HAS MUCH MORE MASS THAN A LARGE BALLOON. SEE NEXT SLIDES. It is also VERY IMPORTANT that they understand volume and mass, by themselves are NOT properties that are useful in identifying matter. This is because any type of matter can have any volume or mass. For example saying you have a kilogram of something is useless in trying to identify what that something is. Likewise, saying you have a liter of something gives you its volume, but alone gives no clue as to what it is. These properties when combined give you density, which is a very strong indicator of what something is. Most materials have fairly unique densities, and from density you can derive the objects specific gravity which is a very strong indicator of its composition. Wood, for instance, can be identified almost exclusively from its Specific Gravity (or density) because each species has a unique SG.
31Big Volume Big MassUSE concrete examples Balloon and lead sinker, golf ball and ping pong ball (same size) which has the greater mass.FYI: scientists define mass as an objects resistance to movement. The harder it is to move, the greater the mass. The easier it is to move (the less force required) It is this resistance to movement that makes a balance (which is just a lever) the correct tool for determining mass. It measure how easy the object is to pick up.
32Really Important Property 3 state or phase of matter at room temp. State or phase of matter refers to:SolidLiquidGasGold is solid at room 68°f.Gold boils at 5085°fGold is melts at 1948°f
33The key question is: AT ROOM TEMPERATURE Is the material you are look at a solid, liquid or gasAT ROOM TEMPERATUREEvery type of matter will be one of these three at room temperature approximately 68°f
34Important Property 3 – state or phase State or phase of matter refers to:SolidLiquidGasI would like to find gaseous gold but couldn’t. I am not sure anyone would want gaseous gold. But it boils at 5085°f. At that temperature and correct pressure gold can become a gas.
35The key question is: AT ROOM TEMPERATURE Is the material you are look at a solid, liquid or gasAT ROOM TEMPERATUREEvery type of matter will be one of these three at room temperature approximately 68°f
36Mass and Volume control two other important properties of matter Weight & Density I have found that all students operating at about third grade level and up can grasp these concepts if they are presented in simple to understand ways.
37Important Weight –The Pull of Gravity on the Object Density – How Much Mass The Thing Has PER UNIT VOLUME
38Weight is the measure of how much the force of gravity pulls down on an object. This mass-weight distinction and connection is one of the key thinks to set straight in the minds of students (according the National Academy of Sciences and the Science Teachers Association) and confusion on this point haunts student all the way through school. So be sure to tackle it now.
40The gravitational pull of earth is defined as 1G The gravitational pull of earth is defined as 1G. The moon, being 1/6th the mass of earth has only 1/6G of pull.Weight = 120kgWeight = 20kg1G1/6GEarthMoon – 1/6 earthBob goes to the moon. Bob on earth, at sea level, at normal temperature and pressure (I don’t know the exact numbers) Weighs 120 Kg.At sea level, under normal conditions, Bobs mass is also 120 Kg. So in most places on earth, we can consider weight and mass as the same.The difference occurs when we move elsewhere in the universe. Example shown here is Bob on earth weighs in at 120kg, but on the moon, which has a mass one sixth that of earth, he weighs 1/6 of 120kg or 20kg. Yet his mass is the same. We didn’t remove any parts of him, so the amount of stuff or matter in him stays the same. If you were to use a balance to measure his mass on the moon, it would show 120kg, but his weight, measured on a scale, would be 20kg. See next slide.
41The BALANCE is different. Lets see why. Earth pulls down at 1G so on the scale you get Weight = 120kgMoon pulls down at 1/6G so on a scale you get Weight = 20kgThe BALANCE is different. Lets see why.Mass = 120kg120kg1G on Each side of BalanceMass = 120kg120kg1/6G on Each side of BalanceBob goes to the moon. Bob on earth, at sea level, at normal temperature and pressure (I don’t know the exact numbers) Weighs 120 Kg.At sea level, under normal conditions, Bobs mass is also 120 Kg. So in most places on earth, we can consider weight and mass as the same.The difference occurs when we move elsewhere in the universe. Example shown here is Bob on earth weighs in at 120kg, but on the moon, which has a mass one sixth that of earth, he weighs 1/6 of 120kg or 20kg. Yet his mass is the same. We didn’t remove any parts of him, so the amount of stuff or matter in him stays the same. If you were to use a balance to measure his mass on the moon, it would show 120kg, but his weight, measured on a scale, would be 20kg. See next slide.MoonEarth
42DENSITYHow much stuff can you fit in a small space
43Not Dense Dense Not much stuff packed into can Density is all about how much you can pack into a small space. If they took me (260lbs of mass) and squished me into a golf ball size object, that object would be much denser than I am. Essentially it is how many subatomic particles are packed into a particular space. The standard size object that we use to measure density is 1 cubic centimeter.A visual demonstration of density is performed by getting a clear plastic glass, fill it with marbles. Measure its mass. Add sand, which fills the spaces. Weight increases but the volume of the glass remains the same. Then add water, water fills the gaps in the sand and thus the same volume gets heavier or more dense.– more mass per given volume.A very good demonstration of this is to get a can of coke and a can of diet coke. Place the coke in a clear tank of water and observe. Place the diet coke in then and see what happens. The coke is full of sugar, which adds a great deal of mass to the same volume. Read the ingredients.Not much stuff packed into canA lot of stuff packed into can
44Other Physical Properties of Matter ColorSmellTasteTextureFlexibilityMalleabilityConductivityReflectanceDuctilityViscosity (if a liquid)Boiling pointFreezing PointPhase at Room TemperatureHomework: have students create a pictionary of the terms listed – term, definition, an illustration picturing the term. They will complain but they can do it.