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

Properties of Atoms Lesson 3

Carbon (C) Nonmetal, fairly unreactive, at higher temperature it reacts with many other elements. (All living or former living substances contain carbon. )

Oxygen (O 2 ) Nonmetal, colorless, odorless, tasteless, and slightly soluble in water. Supports burning and rusting (oxidation). Produced as a waste gas by plants.

Hydrogen (H 2 ) 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 (H 2 SO 4 ) in batteries.

Compound Chemical combination of two or more elements. Can be separated into simpler substances only by chemical reactions.

Sodium + Chloride yields salt (sodium chloride). Uses to flavor foods, Lower melting point of ice, by lowering melting point to 15 o F allows ice to melt at lower temperature than the normal 32 o F.

Salt

Carbon Dioxide (CO 2 ) Colorless gasColorless gas We exhale as a (waste gas). Plants use CO 2 during photosynthesis to produce oxygen (O 2 ).We exhale as a (waste gas). Plants use CO 2 during photosynthesis to produce oxygen (O 2 ). Soluble in water.Soluble in water. Dry ice - solid CO 2.Dry ice - solid CO 2. Used in fire extinguishersUsed in fire extinguishers

Water (H 2 O) 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 absorbs energy it jumps to higher energy levels.As electrons in an atom absorbs energy it jumps to higher energy levels. As it falls back to a lower energy level they emit the energy difference as light.As it falls back to a lower energy level they emit the energy difference as light. (Thus the colors seen in fireworks.)(Thus the colors seen in 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 % Ne % Ne %

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

Changing water to wine.