The Secret of happy living is not to do what you like but to like what you do.

The Secret of happy The Secret of happy living is not to do living is not to do

what you like but to what you like but to like what you do.like what you do.

PropertiesProperties of AtomsLesson 3Lesson 3

Carbon (C)

• Nonmetal, fairly unreactive, at higher temperature it reacts with many other elements.

• (All living or former living substances contain carbon. )

Oxygen (O2)

• Nonmetal, colorless, odorless, tasteless, and slightly soluble in water.

• Supports burning and rusting (oxidation).

• Produced as a waste gas by plants.

Hydrogen (H2)

• Lightest and most abundant element in universe, nonmetal, odorless, tasteless, and colorless gas.

• Very reactive, burns in air, usually not found in free state on earth.

Radon (Rn)

• Radioactive element formed from radioactive decay of Radium (Ra).

Ions• Atom or group of combined

atoms that has a charge because of the loss or gain of electrons.

• Maybe positive (Cations)

• Maybe negative ( Anions)

Ions Cont.• How many electrons in Li+?• 2• Remember (+) means losing

electrons.

• How many electrons in F-?• 10• Remember (-) means gaining

electrons.

Sodium (Na+)• Is a Cation

• Shiny, silvery-white soft, solid, metallic, very reactive with water.

• Coated in wax and stored in oil.

Chlorine (Cl-)

• Is a Anion

• Pale green gas, poisonous gas nonmetal, very reactive.

• Used in bleaches, and plastics.

Electrolyte

• Any compound that conducts electricity when melted or dissolved in water.

• Ex: Ionic compounds, Sulfuric Acid (H2SO4) in batteries.

Compound

• Chemical combination of two or more elements.

• Can be separated into simpler substances only by chemical reactions.

Sodium + Chloride Sodium + Chloride yields salt (sodium yields salt (sodium

chloride).chloride). • Uses to flavor foods,

• Lower melting point of ice, by lowering melting point to 15oF allows ice to melt at lower temperature than the normal 32oF.

Salt

Carbon Dioxide (CO2) • Colorless gasColorless gas• We exhale as a (We exhale as a (waste gaswaste gas). ).

Plants use COPlants use CO22 during during photosynthesphotosynthesisis to produce to produce oxygen (Ooxygen (O22). ).

• Soluble in water. Soluble in water.

• Dry ice - solid CODry ice - solid CO22. .

• Used in fire extinguishersUsed in fire extinguishers

Water (H2O)

• Dihydrogen monoxide - polar molecule.

• Dissolves other polar solutions.• Still considered universal solvent.• • Covers 70% earth's surface and

makes up about 70% of body mass. A raw material used in the process of photosynthesis.

Electron cloud

• Space around the nucleus of an atom where the atom's electrons are found

Cloud Chamber

Lewis Dot Diagram

• A dot is used to represent each valence electron.

• Ex: H

• F• S

Emission Spectrum

• The spectrum of light released from excited atoms of an element.

• As electrons in an atom As electrons in an atom absorbs energy it jumps to absorbs energy it jumps to higher energy levels.higher energy levels.

• As it As it falls backfalls back to a lower to a lower energy level they energy level they emitemit the the energy difference as light. energy difference as light.

• (Thus the colors seen in (Thus the colors seen in fireworks.) fireworks.)

Volatile

• A term used to describe a substance that will change easily to a gas at room temperature.

• Very unstable.

Isotope

• Atoms with the same number of electrons and protons, but different number of neutrons.

Carbon

• Has 3 allotropes.

• Coal• Graphite• Diamond.

Average atomic mass

• Calculated using the % of all identified isotopes.

• Ex: Calculate the average atomic mass of the following:

• Ne - 21 - . 2% • Ne - 22 - 9.3%• Ne - 20 - 90.5%

Work

• (21 x 0.002)• + • ( 22 x .093)• +• (20 x .903)• =

20.183 amu

Changing water to wine.