Atomic Theory
What are the 3 parts of an atom?
Protons, neutrons, and electrons
What are the vertical columns of the periodic table called? What are the horizontal rows called?
Vertical columns = groups/families
Horizontal rows = periods
What are valence electrons?
Valence electrons are the electrons in the outermost shell of an atom. They have the highest energy level and are held most loosely to the atom.
The number of valence electrons in the atoms of an element determines many of the properties of that element, including how it can bond with other atoms.
What is the difference between ionic and covalent bonding?
Ionic bonding = giving and taking electrons
Covalent bonding = sharing electrons
What is matter?
Anything that takes up space and has mass
What is an isotope?
Atoms with the same number of protons and a different number of neutrons
Name 4 properties of metals.
Lustrous, malleable, ductile, good conductors of heat, good conductors of electricity, etc.
Atoms are most stable when they have how many valence electrons?
8 (an octet!)
What is the chemical formula for the ionic compound magnesium oxide?
MgO
3
What is an element's atomic mass?
The average mass of all isotopes of an element
Elements in Group 2 of the periodic table are called...
Alkaline earth metals
What is the electron dot diagram for chlorine?
(Draw on board, just one dot missing)
What makes metallic bonding different from ionic and covalent bonding?
Metallic bonding is an attraction between a positive metal ion and the electrons surrounding it in the “sea” of valence electrons.
What is an alloy?
a mixture made of 2+ elements that has the properties of a metal
What is the difference between atomic number and mass number?
Atomic number = number of protons in the nucleus of an atom (so, the element's number on the periodic table)
Mass number = the sum of protons and neutrons in an atom (how isotopes are identified)
Group 17 (halogens)
What would an atom with one extra (or one less) electron be called?
An ion
What types of elements usually form covalent bonds with each other?
Nonmetals
A covalently bonded molecule in which the electrons are shared unequally is called what?
A polar molecule
How many protons, neutrons, and electrons are in one atom of Carbon-14 isotope? Hint: Carbon's atomic number is 6.
Protons = 6
Electrons = 6
Neutrons = 8
Of the metals, nonmetals, and metalloids, which are most likely to be a gas at room temperature?
Nonmetals
What is the electron dot diagram for table salt?
(draw on board)
What is the chemical formula for the ionic compound aluminum fluoride?
AlF3
What is a precipitate?
A solid that forms from solution during a chemical reaction