How do you know those are examples of matter???

Transcription

1 + What is Matter?? Properties of matter + What is an example of Matter?? How do you know those are examples of matter??? 1

2 + What is Matter?? Matter is Anything that has mass and occupies space (volume) Composed of atoms MASS: The measured amount of material that makes up the object VOLUME: The 3D space taken up by the object + 2

3 + The elephant has more MASS If you pulled each animal with the same amount of force, the elephant would respond less to pulling, even if he didn t pull back at all. That s because an elephant has more mass than a mouse. Mass stays the same no matter what force is acting on the object. This makes mass different from weight, which depends on both the amount of mass and the amount of gravity. This means that even though our elephant weighs less on the moon, his mass stays the same. + Building Blocks of matter ATOM: The smallest unit of an element. Atoms maintain the chemical identity of that element. 3

4 + Building Blocks of matter ELEMENT: a pure substance that cannot be broken down into simpler stable substances and is made of one type of ATOM EXAMPLE: The element carbon is made up of many carbon atoms + Building Blocks of matter COMPOUND: is a molecule that contains at least two different elements. Compounds can be broken down into simple stable substances. 4

5 + Classification of Matter Pure Substance The substance has the same composition throughout Does not vary from sample to sample Mixture Contains more than one substance Varies in composition & properties from sample to sample Classfication Flowchart MATTER yes Can it be physically separated? no no Heterogeneous Mixture (mechanical) MIXTURE Is the composition uniform? yes Homogenous Mixture (solutions) yes PURE SUBSTANCE Compound Can it be chemically decomposed? no Element 5

6 + Types of Mixtures Heterogeneous mixtures Visibly different parts Eg. Chocolate chip cookies; granite Two or more phases (usually) Homogeneous mixtures Different parts not visible (uniform throughout) One phase Eg. Sea water, air Heterogeneous Mixtures 12 Have several different components that are visible to the eye Eg: Raisin Bran 6

7 Homogeneous Mixtures Also known as solutions very small particles ( nm) particles don t settle to the bottom of the container Eg: rubbing alcohol, air, brass alloy + Pure Substances Elements A substance that cannot be separated into simpler substances Compound Two or more elements combined through a chemical reaction Compounds have different properties than elements they re made of 7

8 + Elements Metals Metals: Usually solid at room temp Good conductors of heat and electricity High luster (shiny) Ductile easily pulled into wires Malleable easily beaten into thin sheets High melting point; high density Usually don t combine with each other Readily combine with nonmetals 8

9 Non Metals Nonmetals: Solids (C, P, S, Se, I 2 ); Liquid (Br 2 ); Gases (all others) Poor conductors of heat and electricity; no luster Low melting point; low density Will combine with each other (CO 2 ) Will combine with metals or metalloids Some found uncombined in nature (noble gases) + Metalloids Metalloids Have properties of both metals and nonmetals Some used for semiconductors in electronics Eg: Silicon, Germanium 9

10 + Properties and Changes in Matter Properties Characteristics that can help identify a substance You need to determine more than one property to conclude what the substance actually is Properties are either Extensive or Intensive + Extensive properties Depend on the amount of matter that is present Volume Mass Energy Intensive Properties Do not depend on the amount of matter present Melting point Boiling point Density Ability to conduct electricity Ability to transfer heat 10

11 + Physical Properties Physical Property A characteristic that can be observed or measured without changing the identity of the substance Describing the substance Melting point Boiling point Physical Change - A change in a substance that does not involve a change in the identity of the substance Grinding Cutting melting + The states of Matter Exists in three states on earth Solid Liquid Gas Exists in fourth state in space Plasma (An electrically neutral, highly ionized gas state) 11

12 Solids Definite shape and volume Particles tightly packed in a lattice pattern Crystalline salt, sugar, quartz The particles are packed tightly in an uniform way by strong attractive forces Definite volume Liquids Not a definite shape (Takes shape of container) Particles have more energy Particles can move freely 12

13 Gases Indefinite volume No definite shape(particles bounce off container) Particles have high energy level Particles move independently of one another 13

14 + Physical changes in the state of matter Changes in state does not change what the substance is therefore it is considered a physical change not a chemical change + Chemical Properties Chemical Property- a characteristic that is observed while changing the original substance into a new substance. Wood burning When a substance decomposes in air When a substance will rust 14

15 + Chemical Properties and Chemical Changes The reactants are the substances that react in a chemical change The products are the substances that are formed by the chemical change Carbon plus Oxygen yields (forms) Carbon Dioxide C + O2 CO2 + Evidence of a Chemical Change 15

16 + Energy and Changes of Matter + Chemical Formulas Subscript indicates # of atoms present H 2 O has 2 Hydrogen atoms and 1 Oxygen atom H 2 SO 4 has NaOH has C 6 H 12 O 6 has 2 hydrogen atoms, 1 sulfur atom, 4 oxygen atoms 1 sodium atom, 1 oxygen atom, 1 hydrogen atom 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms 16

17 Separating Mixtures 33 Do NOT cause chemical changes Heterogeneous Mixtures Filtration Separating Mixtures 34 Homogeneous Mixtures Distillation 17

18 Separating Mixtures 35 Homogeneous Mixtures Chromatography Separating Mixtures 36 Homogeneous Mixtures Crystallization 18