ATOMS

1
ATOMS

• Basic building blocks of matter.
• Atoms make up everything (that has mass and takes
  up space).

2
Atomic Structure

• Protons positively charged particles inside the
  nucleus.
• Neutrons neutral particles inside the nucleus
  that have No charge.
• Electrons negatively charged particles in atoms
  found around the nucleus.

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Atomic Particle Size
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Atomic Mass Unit - amu

• Unit of measurement for the mass of subatomic
  particles.
• 1 amu 1.7 X 10 -24 They are TINY!!!
• .000000000000000000000017 grams
• Proton 1 amu
• Neutrons 1 amu
• Electrons almost zero (TINIEST particle with
  the least mass)
• Most mass is in the nucleus with protons and
  neutrons
• Otherwise atoms are mostly EMPTY SPACE

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Atomic Number

• The number of protons inside the nucleus of the
  atom.
• Determines the element.
• Atoms have no charge because the of protons (
  charge) is to the of electrons (- charge).

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Mass Number/Atomic Mass

• The total number of protons and neutrons in an
  atoms nucleus.
• Protons Neutrons Mass Number
• Notice how massive the nucleus is
• compared to the rest of the atom

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Atomic Mass

• The weighted average of the masses of all the
  naturally occurring isotopes of an element.
• Average of Protons Neutrons of all an elements
  Isotopes Atomic Mass

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Electron Levels/Clouds

• Areas around the nucleus where electrons are
  arranged.
• Each level can hold a specific of electrons.
• 1st level - 2 electrons
• 2nd level - up to 8 electrons
• 3rd level up to 8 or 18

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Valence Electrons

• The electrons in the outermost energy level
  (electron cloud).
• What element is this?
• How many valence
• electrons does it have?

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ELEMENTS

• All the atoms that make up our universe
• Identified by the atomic ( of protons)

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3 Main Groups on the Periodic Table
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Metals

• Make up most of the elements
• All solid except Mercury
• Has luster (shiny)
• Good conductors of heat and electricity
• Malleable made into different shapes
• Ductile made into wires

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Metals
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Nonmetals

• Usually gases or brittle solids
• Poor conductors of heat and electricity
• Right side of the periodic table
• Only 17 nonmetals

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Metalloids

• Called Semi-metals
• Share properties of both metals and nonmetals

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Groups/Families

• Columns of the periodic table
• Each element has the same of valence electrons
• The elements share similar chemical and physical
  properties.
• They are each part of the same family

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Periods

• 7 rows on the periodic table
• Consist of elements with the same number of
  electron levels.

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Alkali Metals

• Group 1
• All metals
• 1 Valence Electron
• Very reactive
• Most reactive the only need to lose 1 valence
  electron in chemical bonds

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Alkaline-Earth Metals

• Group 2
• All Metals
• 2 Valence Electrons
• Very reactive but less than group 1.
• Only have to lose 2 valence electrons in chemical
  bonds

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Valence Electrons

• Group 1 all elements
• have 1 valence electron
• Group 2 all elements
• have 2 valence electrons

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Transition Metals

• Groups 3-12
• All metals
• 1 or 2 valence electrons
• Less reactive than group 2
• Also contains lanthanide and actinide series

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Groups 13-16

• Elements change from metals to nonmetals and
  include the metalloids.
• Atoms have 10 fewer valence electrons than the
  group .
• Boron Group 13 - 3 valence electrons
• Carbon Group 14 - 4 valence electrons
• Nitrogen Group 15 - 5 valence electrons
• Oxygen Group 16 - 6 valence electrons

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Halogens

• Group 17
• All nonmetals
• 7 valence electrons
• Very reactive
• Only need to gain 1 more electron for a total of
  8!

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Noble Gases/Inert Gases

• Group 18
• All nonmetals
• 8 valence electrons - except helium only has 2.
• Unreactive
• Have a full outer electron level
• 2 on the 1st level
• 8 on the 2nd level

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Hydrogen stands alone

• 1 valence electron
• Very reactive
• Colorless, odorless gas at room temperature.
• Low density
• Reacts explosively with Oxygen