Chapter 2. Matter and Change 2.1 – Properties of Matter 2.2 – Mixtures 2.3 – Elements and Compounds 2.4 – Chemical Reactions 2.

Chapter 2

Matter and Change

2.1 – Properties of Matter 2.2 – Mixtures 2.3 – Elements and Compounds 2.4 – Chemical Reactions

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Objectives Differentiate and give examples of extensive

and intensive properties Distinguish the three primary states of matter Distinguish physical from chemical change. Classify mixtures as homogeneous or

heterogeneous. Distinguish between elements and

compounds. Memorize the 24 most encountered elements

names and symbols. Distinguish chemical from physical properties

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Extensive Properties

Mass - amount of matter of an object.

Volume - the space occupied by an object.

Extensive Property - a property that depends on the amount of matter in a sample.

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Intensive Properties

a property that depends on the type of matter, not the amount of matter.

Example: Hardness of a rockBoiling point

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Substances

Matter that has a uniform and definite composition

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Physical Properties

Can be observed or measured without changing the composition of a substance

Can be used to identify substances Examples:

HardnessColorMalleabilityBoiling Point

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Identifying Substances

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Physical Changes

Some properties of the material may change, but the composition stays the same

Can be reversible or irreversible Examples:

BoilFreezeBreakCrush

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States of Matter Solid

Definite shape and volume Particles are highly organized and packed close together Not easily compressed

Liquid Definite volume; takes the shape of its container Particles are tightly packed together, but arranged

randomly Not easily compressed

Gas Takes the shape and volume of its container Particles are spaced very far apart Easily Compressed

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States of Matter

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Vapor

the gaseous state of a substance that is generally a liquid or solid at room temperature

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Classification of Physical Changes some properties of a material change

the composition of the material remains the same

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24 Common Elements

Carbon C Aluminum Al Copper Cu (from cuprum)

Fluorine F Bromine Br Iron Fe (from ferrum)

Hydrogen H Calcium Ca Lead Pb (from plumbum)

Iodine I Chlorine Cl Mercury Hg (from hydrargyrum)

Nitrogen N Helium He Potassium K (from kalium)

Oxygen O Lithium Li Silver Ag (from argentum)

Phosphorus P Magnesium Mg Sodium Na (from hatrium)

Sulfur S Silicon Si Tin Sn (from stannum)

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Mixture physical blend of two or more

components

heterogeneous mixture – composition is not uniform throughout (2 or more phases/part)

homogeneous mixture – the composition is uniform throughout is a (single phase/part)

Also known as a solution.

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Separating Mixtures

Filtration - separates a solid from the liquid in a heterogeneous mixture

Distillation – a liquid is boiled to produce a vapor that is then condensed into a liquid.

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Elements vs. Compounds element – the simplest form of matter

that has a unique set of properties.

compound – a substance that contains two or more elements chemically combined in a fixed proportion.Properties of the individual components are

different than the properties of the compound

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Distinguishing Substances & Mixtures

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Chemical Reactions

Chemical Property ability of a chemical to undergo a chemical

change

Reactant – substances that undergo change

Products – New substances

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Chemical Changes produces matter with a different

composition than the original matter

Evidence of a changeEnergy TransferColor ChangeProduction of gasProduction of a precipitate

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Law of Conservation of Mass Matter is neither created or destroyed; it

is only changed

Mass of the products = Mass of the reactants

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