Download CHEMISTRY

CHEMISTRY
For DUMMIES
(you’re not dummies)
This is just a dumb lecture.
Chapter 2
What you were supposed to learn in
ICS or Chemistry last year.
Everything in the universe is made of matter.
But what is MATTER?
Nucleus contains:
PROTON: (+) & 1 AMU
NEUTRON: neutral & 1 AMU
Outside the nucleus:
ELECTRON: (-) & no AMU
THE ATOM
IS THE BASIC UNIT OF MATTER
ATOM = The Dodger’s Stadium
NUCLEUS = baseball (pencil eraser) on the
pitcher’s mound (contains protons & electrons)
ELECTRONS = seating… even nose-bleed seats
The periodic table of elements shows all the
types of matter known to man.
ELEMENTS are pure substances that cannot be
broken chemically into simpler kinds of matter.
Each square
shows the:
chemical symbol,
atomic number,
& atomic mass.
Ex. Carbon is
C
6
12
Atomic # =‘s # of protons
# of electrons
Atomic mass = protons + neutrons
Biology is cool because we don’t need to memorize all
100+ elements… we only need to be concerned with
The 6 chemicals of LIFE… (What you need to live.)
Carbon
Hydrogen
Nitrogen
Oxygen
Phosphorus
Sulfur
SUMMARY:
• The ATOM is the smallest unit of matter.
• All atoms are basically the same:
1. protons (+) & neutrons (no charge) IN
NUCLEUS
2. electrons (-) OUTSIDE the NUCLEUS
3. NEUTRAL OVERALL (#p=#e)
4. When atoms gain or lose electrons they
become IONS- they have a charge.
Ex. a Hydrogen atom that loses it’s
electron is called a hydrogen ion, H+,
or a proton.
CHEMISTRY
IS THEbut
STUDY
OF
Sort
of like psychologyfor atoms.
THE BEHAVIOR OF ATOMS… OF
MATTER.
1.
2.
3.
4.
5.
WHAT HAVE CHEMISTS LEARNED???
The nature of most atoms is that they are LONELY
and sometimes AGGRESSIVE!
Most atoms team up with or overtake other atoms in
an attempt to get the “right” number of electrons. This
is how molecules are formed.
Only the NOBLE GASSES can exist on their own.
ATOMS will switch partners when provoked. This is
what chemical reactions are all about.
Don’t mess with an atom’s nucleus.
MATTER EXISTS IN DIFFERENT FORMS DEPENDING ON
ITS OWN PERSONALITY AND ITS ENVIRONMENT.
See above: States of Matter… Temperature can influence this.
one
column
of
elements
is
NONREACTIVE
(noble gasses).
The rest stick together through various
Kinds of bonds… and so we
Have “matter” that is big enough to see.
COMPOUND
ex. water, saltNaCl, glucose
Pure substance
that is made
up of atoms of
two or more
elements.
Water molecules
MOLECULE
Ex. oxygen (O2)
Water, glucose, carbon dioxide etc.
the simplest part
of a substance
that retains
all the properties
of the substance
and that can exist
in a free state.
Oxygen gas is a molecule but not a
Compound because it is only made from
one kind of element… two oxygen atoms
Are held together through a double bond.
BONDING… 2 BASIC TYPES OF
BONDS.
COVALENT BOND
Atoms share their
electrons to reach the
MAGIC NUMBER
2 or 8.
Both hydrogens
are sharing their
one electron so both
now have two.
THIS IS HOW HYROGEN
GAS EXISTS IN NATURE.
2 TYPES OF COVALENT BONDS:
Nonpolar covalent bond- electrons are
shared equally because both atoms
have an equal pull on the electrons.
Ex. Oxygen O=O or Hydrogen H-H
Polar covalent bond- electrons are NOT
shared equally because one atom is
more electronegative than the other.
Ex. Water H-O-H
IONIC BOND
Electrons are exchanged.
Both become IONS
Opposites attract!
Ex. Chlorine STEALS an
Electron from Sodium.
Na+ Cl-
Gaining an electron
Makes the atom a
Negative ion w/ a
Charge of -1
(anion)
Losing an electron
Makes the atom
A positive ion w/ a
Charge of +1
(cation)
GAIN OR LOSE ELECTRONS…
CHEMICAL REACTIONS…
what are they?
• SIMPLY PUT… they
are atoms switching
groups or clique’s.
• Bonds get broken.
• Bonds are formed.
• Rxns can release or
require energy.
Chem rxn for photosynthesis:
6CO2 + 6H20 + light  C6H12O6 + 6O2
EXERGONIC Rxns RELEASE ENERGY
ex. burning a candle or cell respiration
ENDERGONIC Rxns. REQUIRE ENERGY
ex. .Photosynthesis
ACTIVATION
ENERGY
Amount of energy
needed to start
a spontaneous
chemical reaction.
HERE’S A REACTION WITH A HELPER…
A CATALYST lowers the amount of activation
energy needed to start a reaction .
ENZYMES are biological catalyst.
SOLUTIONS are easy to
understand…
• Solute = kool-aid
• Solvent = water
• Solution = drink
Cell contents are solutions…
so is your blood
SOLVENT = water
SOLUTES=
glucose, ions like
Cl-, Ca+, Na+, H+
Urea (cell waste),
proteins,
hormones
The pH scale is a scale showing the relative
amounts of (H+) Hydrogen and (OH-) Hydroxide
ions in a solution.
The pH
of a solution
will influence
the shape of
proteins in that
solution