# MIDTERM REVIEW WORKSHEET

```MIDTERM
REVIEW
WORKSHEET
OPEN BOOK
30 POINT QUIZ
To Be Turned in at your Midterm
Components of an Experiment
Independent Variable: The factor in the experiment
that is purposely changed.
“I” the examiner change
Dependent Variable: Measurable factor that
responds to a change in the independent variable.
Dependent depends on the independent.
Constant- Conditions that remain the same during
the course of the experiment
Control- A standard for comparison, not in every
experiment.
**Remember how to
choose the
Independent variable
(what “I” the examiner
change),
Dependent variable
(depends on the
independent- usually
measurable),
Constants (remains
the same),
Control (standard to
compare to) etc.
How to Graph “Effect of IV on DV”
Scientific Method
• A series of logical steps that are followed to
solve a problem.
• Uses critical thinking
PIE CHART- parts of a whole, %
Bar Graph- Comparison of similar data
for several different items or events
LINE GRAPH:
For displaying data that changes over time
Metric Conversion of Units
Base:
Meter
Liter
Gram
by
Metric Conversion Units
Accuracy vs Precision
MATTER
Substance
Element
Compound
Mixture
Heterogeneous
Mixture
Homogeneous
Mixture
‘Solutions’
Atom:
Molecule:
Examples:
Examples:
Examples:
Examples:
MATTER
PURE
SUBSTANCE
• Matter that has a fixed
composition (makeup) and
definite properties (chemical
and physical).
• Are chemically combined- so
they can’t be physically
separated.
MIXTURE
• Matter that is a combination
of two or more pure substances
that do not have a fixed
composition or definite
properties.
• Are NOT chemically combined,
so components CAN be
separated.
Compound:
of 2 or more different
elements that are
chemically combined.
Element:
A substance that can’t be
broken down into
simpler substances
only one kind of atom.
ATOM:
The smallest unit of an
element that maintains the
properties of the element.
MOLECULE:
H2O
O2
The smallest unit of a
substance that behaves like
the substance.
(Keeps all of its physical and
chemical properties)
Changes of State
PHYSICAL
CHANGE
A change of
matter from one
form to another
without a
change in
chemical
properties
•
•
•
•
•
•
Dissolving
Sanding
Crushing
Breaking/cutting
Bending/twisting
Mixing
• CHANGE OF STATE
– Melting/evaporating
– freezing
CHEMICAL
CHANGE
A change of
matter that
occurs when a
substance
changes
composition by
forming one or
more new
substances
•
•
•
•
•
•
•
ODOR
COLOR CHANGE
BUBBLING
FIZZING
FOAMING
HEAT PRODUCED
SOUND PRODUCED
CANNOT BE REVERSED
BY PHYSICAL CHANGES
Changes of State
Buoyant Force
The buoyant
force is equal
to the weight
of the liquid
displaced.
Archimedes Principle
An object that is
submerged in a fluid
is buoyed up by a
force equal to the
weight of the fluid
that is displaced
Density
D = M/V
mass
volume
Pascal’s Principle
A change in
pressure at any
point in an
enclosed fluid at
rest is
transmitted
equally
throughout the
fluid.
V
I
S
C
O
S
I
T
Y
Pressure
Temperature
and
Volume
Boyle’s Law, Charle’s Law of Gases:
Constant Temperature: If you decrease the volume
you will increase the pressure.
Constant Pressure: If you increase the temperature
the volume will increase (if it could).
Bohr’s Model of the Atom
Like planets around the sun
Periodic Table
METALS
NONMETALS
METALS
•Alkali Metals
•Alkali Earth Metals
•Transitions Metals
•‘Other Metals’
Form Cations
+
NON-METALS
•‘Other Non-Metals’
•Halogens
•Noble Gases
Form Anions
-
ATOMIC NUMBER =
Number of
Protons =
Number of
Electrons
MASS NUMBER =
(Atomic Mass, Atomic Weight)
Number of Protons +
Number of Neutrons
Atomic Number +
Number of Neutrons
Using the Periodic Table
ELEMENT
NAME AND
SYMBOL
ATOMIC
#
(P)
MASS
NUMBER
(round to
nearest
whole
number)
NUMBER
of
PROTONS
NUMBER
of
NEUTRONS
NUMBER
of
ELECTRONS
15
38
Gallium
(Ga)
31
NUMBER OXIDATION
of
NUMBER
VALENCE
and
ELECTRONS CHARGE
(+ or -)
Using the Periodic Table
ELEMENT
NAME AND
SYMBOL
ATOMIC
#
MASS
NUMBER
(round to
nearest
whole
number)
NUMBER
of
PROTONS
NUMBER
of
NEUTRONS
NUMBER
of
ELECTRONS
31
70
31
39
31
NUMBER OXIDATION
of
NUMBER
VALENCE
and
ELECTRONS CHARGE
(+ or -)
Phosphorus
(P)
Strontium
(Sr)
Gallium
(Ga)
3
+3
Remember: Atomic number is = the number of Protons
In a Neutral Atom the number of = protons is = to the number of – electrons
All the Mass in in the nucleus- The Mass Number is = Protons + Neutrons
Valence Electrons = outer shell = Group 1 has 1, Group 2 = 2, Group 13 = 3, Group 14 = 4 etc
Oxidation # = # of electrons taken in (-) or give away (+) to get to a full valence shell.
Dalton's Atomic Theory
• 1) All matter is made of atoms. Atoms are
indivisible and indestructible.
• 2) All atoms of a given element are identical in
mass and properties
• 3) Compounds are formed by a combination
of two or more different kinds of atoms.
• 4) A chemical reaction is a rearrangement of
atoms.
This chart and a
Periodic Table will
be provided to youyou just have to
it and USE it.
Practice with your
class worksheets,
quizzes and
homeworks
Organic Compound
A COVALENTLY bonded compound
that contains carbon
Most common elements:
C,H
ANY organic compound that
is burned will release
Carbon in some form
Hydrocarbon
of only carbon and hydrogen
Simplest Hydrocarbon:
Methane
Alkanes, Alkenes, Alkynes
Only Single Bonds C-C
At least one Double C=C
At least one Triple C=C
POLYMERS
Polymers are substances that are
made up of a large number of
repeating units (monomers). There
are both synthetic and naturally
occurring polymers.
Formed by chemical reactions in
which these monomers are joined
in a certain order, forming a chain.
Natural Polymers:
Proteins - silk, collagen, keratin, DNA
Repeating units of amino acids
Carbohydrates - cellulose, starch. Made up
of repeating units of glucose
Other Natural polymers: Rubber
(hydrocarbon base) and silicones
(alternating silicon and oxygen).
Cross linking: Makes the polymer elastic,
flexible by helping it to go back to its
original shape after stretching.
Too many cross links and the polmer
becomes rigid (like the back of a desk
chair), or may even crack/break
Counting Atoms
2H2O
= 2 Molecules of H2O,
or 4 atoms of H, 2 atoms of O,
6 atoms all together
Co
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