Elementsthe building blocks of all matter

The most important element is probably carbon. It has

absolutely unique properties in the fact it can link to itself and form

literally billions of different chemicals. Some of them have

even become living matter. Inorganic carbon can exist as a

diamond, both very beautiful and the hardest material known.

The most beautiful element is probably Gold. It is unique in the

since it is both metallic and colorful. Unlike Copper (which can also be very beautiful), Gold does not tarnish or corrode. It is

also so soft it can be finely polished just by rubbing it.

The most fascinating element is probably Mercury. It is the only metal which is fully liquid

at room temperature. Unfortunately, unlike Carbon or Gold, Mercury is poisonous. Radium

can also bedazzle people. A concentrated solution of radium chloride glows with a soft, blue

phosphorescence. Close inspection reveals a galaxy of tiny stars twinkling throughout the

glowing liquid. However, Radium is far more dangerous than Mercury because it is so terribly

radioactive. The scientist who discovered it (Curie) eventually died of leukemia, most likely

due to radiation exposure.

The most useful element is Iron, of course. It is easy to make and

the properties of the metal can be fine tuned by alloying it with

carbon and/or other metals. The creation of the Japanese Samurai sword is a fascinating study in the

combination of high and low carbon steel into a remarkably effective and elegant weapon.

The strangest element might just be Francium. It is formed by the radioactive decay of larger atoms, but Francium itself has a half life

of only about 10 minutes. Francium exists, but only as single atoms dispersed throughout the universe which suddenly appear

like soap bubbles and then disappear just as quickly.

The most abundant element is Hydrogen. Most of the universe is made of this gas. The human

body is mostly water, and because water is 2/3 hydrogen, humans are also mostly made of hydrogen as

well.

The Elements

• 116 known elements• 94 occur naturally

-22 artificially made by nuclear processes

Properties of Metals

• Metals are good conductors of heat and electricity.

• Metals are shiny.• Metals are ductile (can be

stretched into thin wires).• Metals are malleable (can be

pounded into thin sheets).• A chemical property of metal is

its reaction with water which results in corrosion.

Properties of Non-Metals

• Non-metals are poor conductors of heat and electricity.

• Non-metals are not ductile or malleable.

• Solid non-metals are brittle and break easily.

• They are dull.• Many non-metals are

gases.Sulfur

Properties of Metalloids

• Metalloids (metal-like) have properties of both metals and non-metals.

• They are solids that can be shiny or dull.

• They conduct heat and electricity better than non-metals but not as well as metals.

• They are ductile and malleable.

Silicon

The Periodic Table

Compound

• Two or more elements chemically combined in specific proportions

• Examples:– Water H2O

– Salt NaCl

– Sugar C6H12O6

Chemical Formulas are used to represent compounds

CompoundsOrganic

• contain carbon

• produce smoke or soot when heated

-ex. Acetic acid

ascorbic acid

ethanol

propane

Inorganic• some contain carbon but

it evolve to gaseous compounds

• form white residue when heated

-ex. Water

baking soda

ammonia

hydrochloric acid

• 95% of living organisms is made of: carbon (C) oxygen (O) hydrogen (H) nitrogen (N)

Elements of Life

*water- most abundant compound*human body= 80%

Indicator- tool to classify compound

(distinct colors when mixed w/ acids, base or salt.)

•Acid

-sour

-red to blue

-colorless

(ph indicator)

•Base

-bitter

-blue to red

-purple

Classifying mixtures

Mixtures may be either:

Solutions

Colloids

Suspensions

Solutions

• Have small particles

• Are transparent (not the same as colorless)

• Do not separate

• Water solutions are very common in

biological systems

– Examples: salt water, kool-aid, air, brass, vinegar

Colloids

• Have medium size particles

• Do not separate

– Examples: fog, whipped cream, milk, cheese,

mayonnaise

*Tyndall effect- involves scattering of light by

colloidal particles

Suspensions

• Have very large particles

• Settle out (separates into layers)

– Examples: blood platelets, muddy water,

calamine lotion, oil & water, Italian salad

dressing

Separating mixtures

• Filtration and decantation

• Evaporation

• Centrifugation

• Simple and fractional distillation

• Magnetic separation

• Flotation

• Sublimation

• Chromatography

Filtration and decantation

Evaporation

Centrifugation

Simple and fractional distillation

Laboratory Distillation Setup

Stone chips are added into the

liquid to allow even and uniform boiling

Cold and hot water enters from the bottom and top of

the condenser respectively. Water will gain heat as vapour condenses. Warmer water is less effective in condensing

vapour

Thermometer at the entrance of the

condenser indicates the boiling point of the type of vapour

entering it

Magnetic separation

Flotation

Sublimation

Chromatography

Mixture Components

Separation

Stationary Phase

Mobile Phase

(1) Mixtures added at the

base line

(2) Paper dipped into solvent for mixtures

(3) Component will run along

paper as it dissolves in

solvent

Components of Essential Oils are separated

Separation of Mixtures

• What are the components in mixture X?

RedX Yellow BlueX Contains Red and Yellow Components

Separation of Mixtures

• How do you separate a mixture of salt, sand and iron?

Salt

Salt

Salt

Iron

IronIronN S

Sand

Sand

Sand

•Magnetic attraction to get iron filings

•Add water to dissolve salt

•Filter to get sand residue

•Evaporate filtrate to get salt