Chemistry * The Study of Matter - SchoolWorld an Edline Solution

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Chemistry –

The Study of

Matter

Alchemists hard at work.

Chemistry

The study of the composition, structure, and properties of matter and the changes it undergoes.

Branches:

Organic

Inorganic

Physical

Analytical

Biochemistry

Theoretical

Research –

What are some ‘modern technologies’ that have impacted the way we live?

Basic Reasearch

Increasing knowledge

Applied Research

Solve a specific problem

Technological Development

Production and use of products to improve quality of life

Matter

4 states of matter

Solids

Liquids

Gases

Plasma

Kinetic Molecular Theory (KMT)

All matter is made of particles that are in constant motion

Solids

Very low KE – particles vibrate

Fixed shape

Fixed volume

Liquids

Low KE – particles can move around but are close together

Variable shape

Fixed volume

Gases

High KE – particles separate and move freely

Variable shape

Variable volume

Plasma

Very high KE

 particles collide with enough energy to break into charged particles

Gas-like – variable shape and volume

Ex: stars, fluorescent light bulbs

The Four States of Matter

Solid, Liquid, Gas, and Plasma

Phases of Matter

Intensive v. Extensive

Properties

Intensive property does NOT depend on sample size.

Ex: density, melting point

Extensive property does depend on sample size.

Ex: mass, volume, energy

Physical Properties and

Changes

Can be observed without changing the identity of the substance

Examples:

Color

Viscosity

Melting and boiling points

Thermal conductivity

Electrical conductivity

More Examples:

Specific heat

Luster

State of matter

Phase changes

Magnetism

Solubility

Malleability

Ductility

Crystal Form

Tenacity

Solid

Melting

Freezing

Deposition

Sublimation

Liquid

Condensation

Evaporation

Gas

Chemical Properties and

Changes

Ability to change into a new substance

Reactants become products

Examples:

Flammable

Rusting

Reactivity

Oxidation

Acidity/basisity

Corrosion

Inert

Name that property

Honey and motor oil are very slow to pour. What property bests describes this property???

Viscosity

What property of liquids would you look for to start charcoal for a BBQ????

Flammability

Iron heats up faster than aluminum. What property is this????

Specific Heat

Name that property (more)

Paints made of silver are applied to the back of mirrors. What property of silver is useful????

Luster

The copper on the Statue of Liberty has turned green. What property is causing this???

Corrosion or Oxidation

Jewelry can be pounded to form artistic designs.

What property is this????

Malleability

Name that property (still)

A good frying pan heats food evenly. What property of frying is this????

Thermal Conductivity

Quartz forms hexagons and diamonds form cubes.

What property is this???

Crystal Form

You purchase a clear stone that might be a diamond.

What simple test can you make to determine if it is actually a diamond???

Hardness

Name that property (lastly)

You accidentally drop an iron bolt into a hard-to-reach place in your automobile engine. What property of iron enables you to retrieve the bolt without having to find someone with small hands?

Magnetism

All chemical and physical changes require

ENERGY!!!

Chemical and Physical Properties

Energy & Phase Changes

Heat of vaporization - Amount of heat needed to change a liquid into a gas at its boiling point

Heat of fusion - Amount of heat required to melt a solid at its melting point

Classification Flowchart

yes

MATTER no

Can it be physically separated?

PURE SUBSTANCE MIXTURE yes

Is the composition uniform?

Homogeneous

Mixture

(solution) no

Heterogeneous

Mixture yes

Can it be chemically decomposed?

Compound Element no

Colloids Suspensions

Classification of Matter

Examples:

Graphite

Pepper

Sugar (sucrose)

Paint

Soda

Element

Heterogeneous mixture

Compound

Heterogeneous mixture

Solution (homogeneous mixture

Pure Substances

1.

Element

Composed of identical atoms

Ex: Copper wire, aluminum foil

2.

Pure Substances

Compounds

Composed of two or more elements in a fixed ratio

H

O H

H

C

H

C

C

H

O H

C

H

O H

O

H

C

O

H

Properties differ from individual elements

Ex: glucose, caffeine

C

H

O H

Mixtures

1.

2.

3.

Combination of 2 or more pure substances

Homogeneous mixtures

Colloids

Heterogeneous mixtures

Suspensions

Mixtures

1.

Homogeneous

AKA: Solution

Very small particles that do not settle

No Tyndall effect

Ex: rubbing alcohol, salt water

Mixtures

2.

Colloid

Heterogeneous

Medium sized particles that do NOT settle

Tyndall effect

Ex: milk

colloid solution

Which glass contains a colloid?

Colloids scatter light, making a beam visible.

Examples of Colloids

Fog, aerosol sprays

Smoke, airborne bacteria

Whipped cream, soap suds

Milk, mayonnaise

Paint, clays, gelatin

Marshmallow, Styrofoam

Butter, cheese

Dispersing

Medium

Gas

Dispersed

Substance

Liquid

Gas

Liquid

Liquid

Liquid

Solid

Solid

Solid

Gas

Liquid

Solid

Gas

Liquid

Colloid Type

Aerosol

Aerosol

Foam

Emulsion

Sol

Solid foam

Solid emulsion

Mixtures

3.

Suspension

Heterogeneous

Large particles that will settle

Tyndall effect

Ex: fresh squeezed lemonade

Mixtures – Colloid, suspension, or solution??

Examples

Mayonnaise

Muddy water

Fog

Salt water

Italian salad dressing

Colloid

Suspension

Colloid

Solution

Suspension

The Periodic Table

Rows – Periods

Columns – Groups or Families

1.

2.

3.

Three main types of elements

Metals

Nonmetals

Metalloids

Metals

Conducts heat and electricity

Malleable

Ductile

Nonmetals

Many are gases at room temperature

Solids are brittle

Metalloids

Touch the stair-step line (except Al)

Some characteristics of metals and nonmetals

Semiconductors

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