Download Chemistry in 7 Days

Chemistry in 7 Days
• The basic unit of chemistry is the atom
• The atom has protons and neutrons in the
nucleus and electrons orbiting the nucleus.
• Electrons have a negative charge, protons
positive, and neutrons are neutral
Add Illustration of atom
Atoms
• The number of protons and the number of
electrons should equal each other, or you
have an ion with a charge (+ or -)
Pic of ion
Elements
• Elements are atoms with the same number
of protons. Because they have the same
number of protons and electrons they have
the same chemical characteristics
• Isotopes are atoms with differing numbers
of neutrons. They are the same chemically
Lab
• Lab 5A, p 47, inside the atom
Periodic table
• The periodic table is an orderly arrangement
of the elements based on the number of
protons in the atoms of that element.
• This is known as the atomic number
• A period is a row across the table
• A group or family is a column up and down
the table
Groups and families
• Groups and families have similar
characteristics because they have the same
number of electrons in the outer level (they
look the same to other atoms)
Periods
• Periods, the rows across the periodic table,
have the same number of electron orbitals
or shells or levels
Lab 6C
• P 57, Valence
Pic of electron orbitals
Joining atoms
• Ionic bonds- one atom takes electrons from
the other. They have positive and negative
charges and stick together like magnets.
• Covalent bonds-They share electrons
• Both types of bond are an attempt to have a
full outer level of electrons. That’s how
atoms are most stable.
Pics of ionic and covalent bonds
Naming chemical compounds
• Systematic Nomenclature:
• For names start with element to the left side
on the periodic table
• add -ide to the second element
More Naming
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use Greek prefixes for number of atoms:
mono, di, tri, tetra, penta, hexa, hepta,
octa, nona, deca
Example:
CO carbon monoxide
CO2 carbon dioxide
N2O5 dinitrogen pentoxide
Physical and chemical change
• Physical change-substance is the same
• Chemical change- a new substance
(chemical) is formed
Physical Change
• Lab 4A , p 37, Phase changes of water
Essay Questions
• Thoroughly explain why the members of
the same groups and families on the
periodic table react in a similar manner.
• What is the difference between an ionic
bond and a covalent bond?
Chemical Equations
• Equations are a representation of a chemical
reaction
• 2H2 + O2 = 2H2O
• The numbers of atoms of each type must be
the same on each side
• Start by balancing an element that
appears in only one reactant and
product.
• Once one element is balanced, proceed
to balance another, and another, until
all elements are balanced.
• Balance chemical formulas by placing
coefficients in front of them. Do not
add subscripts, because this will
change the formulas.
Try this one
• 1. CH4 + O2 ->CO2 + H2O
Did you get this?
• 1. 1 CH4 +
2 O2 1 CO2
+ 2 H2O
Water and Solutions
• Water is very important in chemistry
• It enables chemicals to react with each other
• It is so important is almost a science on its
own
• So why is water so important in so many
chemical reactions?
Water
• Unique polar molecule, it is the universal
solvent
• Dissolved in a liquid, molecules can move
much more freely than as a solid
Acids and Bases
• Acids – Force an “H-” on a substance
• Bases – Rip an “H-” from a substance
• pH = the negative log of the hydronium ion
(H3O+) concentration
• pH scale from 0 to 14
• 0 is very strong acid, 14 very strong base, 7
is neutral
• Each number is a factor of 10 from the next
Solutions
• Concentration vs dilution
• Do a serial dilution in SEPUP tray
• Lab 9B, Solutions and Beer’s Law, p 69
pH scale
• Lab 13 A p101
• Serial dilution in SEPUP tray
Electro Chemistry
• Works in solutions and with ions
• Lab 15B, p 124