Chemistry - schultz915

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Mrs. Schultz
 Website:
 schultz915.pbworks.com
 Phone:
 e-mail:
741-3366 x2129
[email protected]
Means
“to know”
from Latin scientia
*Gathering information through observation
*Organizing information by looking for regularities
*Wondering why the regularities exist
*Communicating the findings to others
Uses the senses to gather information
(sight, sound, taste, touch, smell)
2 types:
1. Qualitative: general characteristics using senses
Ex/ The wire is shiny and silver in color.
2.Quantitative: Makes a measurement using tools
Ex/ruler for length, graduated cylinder for volume
1.Vague – having no point of reference
Ex/ Obtain 5 hydrochloric acid.
How much?
2.Defined – having a point of reference
Ex/ Measure 5 mL HCl
* ALL MEASUREMENTS need number,
units, and label.
 The
study of matter is chemistry.
 This course will study…
structure, composition, properties, the changes
that matter undergoes, and the energy
changes that accompany these processes.
 Considered the central science because both
living and nonliving matter consist of chemical
structures.
1.volume is the amount of three
dimensional space an object occupies.
2. mass is a measure of the amount of
matter in an object.
matter is anything that has mass and takes
up space
 Any
substance that has a definite
composition.
 It is always made up of the same atoms
no matter where it came from.
 Ex/ water, table sugar, carbon dioxide
1.Organic chemistry – study of carbon
containing compounds
2.Inorganic chemistry – study of
compounds that do not contain carbon
3.Physical chemistry – study of the
properties and changes of matter and
their relation to energy
 4.Analytical
chemistry –
identification of the components and
composition of materials
 5.Biochemistry – study of substances
and processes occurring in living
things
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conducted for the sake of increasing knowledge only
and not to meet practical goals.
ex/ why a specific reaction occurs
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Conducted to meet goals defined by specific needs
This research is driven by a desire to solve a certain
problem.
ex/ new refrigerants developed because of
damage to ozone layer
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Employs existing knowledge to make life easier or
more convenient
ex/ computers and biodegradable materials
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A logical approach to solving problems by
observing and collecting data, formulating
hypotheses, testing hypotheses, and the
formulation of theories that are supported by
data.
Experiments are proscribed procedures that collect data
to support a hypothesis.
Experiments have variables:
independent variable – manipulated (variable you
change in an experiment)
dependent variable – responding (variable observed
during experiment)
A well-tested explanation for a broad set
of observations.
Ex/ Atomic theory is useful because it
helps to form a mental picture of atoms.
Note: Theories are not proven. They are
supported by data.
Model - An explanation of how
phenomena occur and how data and
events are related.
Models are visual, verbal, & mathematical.
 Ex. Atomic Model shows structure &
composition of atoms
Statement that summarizes the results of many
observations and experiments.
3 important chemical laws:
 Law of Conservation of energy
 Law of Conservation of mass
 Law of Conservation of matter
*ALL LAWS FOLLOWED IN CHEMICAL REACTIONS
Matter
and Its
Properties
atom: simplest particle of matter, which
keeps identity of element.
element: made of only one type of atom
 ex/ oxygen is considered an element
because it is only composed of oxygen
atoms.
compound: made of more than 1 type of atom
linked together.
ex/ water, sodium chloride (table salt)
molecule: smallest particle of a substance
retaining the properties of the substance.
ex/ 2 H atoms and 1 O atom are bonded
together in water to form a unit.
Extensive properties depend on the amount of
matter that is present.
 ex/ volume, mass, amount of energy in a
substance.
Intensive properties do not depend on the
amount of matter present.
 ex/ melting point, density, ability to conduct
electricity
Physical Property- can be observed without changing
the identity of the substance.
 physical properties describe the substance itself
 examples: boiling point, melting point, density
 A change in a substance that does not involve a
change in the identity of the substance is called a
physical change. (ex/ tearing, grinding, cutting)
Chemical property: property of a substance related to
a chemical change that the substance undergoes.
 ** CAN NOT BE OBSERVED WITHOUT CHANGING
THE IDENTITY OF THE SUBSTANCE.
 *This means the substance has to go through a
chemical reaction.
 A change in which one or more substances are
converted into different substances is called a
chemical change or chemical reaction.
 Ex. Rusting, corrosion, sour milk
 substances
that react (enter) in a
chemical change are called the
reactants.
 substances that are formed by the
chemical change are called the products.
 Mass, matter and energy are conserved
in a chemical reaction (change).
 1.
What is the reactant in the
chemical reaction above?
 Ans. Copper(II) oxide
 2. What are the products?
 Ans. Copper & oxygen
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A change of state is a physical change of a substance
from one state to another.
Most matter is found in one of the following 3 states:
GAS: No fixed volume, no fixed shape, assumes shape
of container, & particles weakly attracted to each other
and move independently at high speed.
LIQUID: Definite volume, no shape of its own, assumes
shape of container, & particles slip past each other.
SOLID: fixed volume, fixed shape (held tightly in a rigid
structure), vibrate only slightly
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4th State: PLASMA is a high temperature physical state
of matter in which atoms lose their electrons.
ex/ found in a fluorescent bulb
5th State: BOSE-EINSTEIN CONDENSATES: matter has
different properties at very low temperatures.
Steps:
1.
Put test tube in test tube rack.
2.
Place a piece of copper in the test tube
3.
Using the pipette, put nitric acid in the test tube. Put enough
acid to cover the copper.
4.
Return to your lab area & put the test tube rack on the high
bench to observe until the reaction is complete.
5.
Place the product of the reaction in the waste container.
6.
Rinse out test tube with water, return materials, clean up
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Make a data table of observations that include before, during,
and after the chemical reaction.
Answer 4 questions (on the next slide)
Copper + nitric acid  copper(II) nitrate + nitrogen dioxide + water
1. What are the reactants?
2. What are the products?
3. List 3 observations that support that a chemical
change occurred?
4. What chemical property of copper is demonstrated?
All matter can be classified into two groups:
pure substances or mixtures.
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A pure substance can be an element or compound. Its
composition is the same throughout and does not vary
from sample to sample.
ex/ iron, carbon dioxide, sugar
Mixture- a combination of 2 or more substances (each
substance in mixture retains individual properties)
ex/ air- mix of gases: O2, CO2, H2O, N2, H2
Heterogeneous mixture: (Greek heteros= different; genos=
kind) A mixture that is not uniform in composition. ex/ Soil
has clay, sand, silt, & decayed material.
2 Types of Heterogeneous Mixtures:
Suspension- mixture containing relatively large particles;
particles remain suspended for a while after stirring, but
then settle out. ex/ Italian dressing
Colloid- liquid mixture containing very small particles that do
not settle out, even with time.
ex/ milk- fat molecules are dispersed throughout the liquid
Homogeneous Mixture (Greek: homos= same)
A mixture that is completely uniform in composition.
Chemists call homogeneous mixtures: SOLUTIONS
Homogenous mixtures consists of a single phase (solid,
liquid, or gas)
 ex/ tap water, energy drinks, brass key
Periodic Table: table in which elements, arranged in
order of atomic number, are placed so that those with
similar properties are near each other.
Period: horizontal  rows of elements in periodic
table.
• 7 periods of elements on the Periodic Table
Group (or family): vertical columns that each contain
elements with similar properties
• 18 groups on the periodic table
Elements are symbolized by one or two letters

What element is symbolized by W? Cu? Au? Ag?
Metals
-usually solid (except Hg)
phase
-shiny (luster)
-malleable- flattened or shaped
-ductile- drawn in wire
-conductors of heat
& electricity
-react w/ acid + base
-located on the left side
of the periodic table
Non Metals
-can be any phase
-dull
-brittle
-non conductors
-don’t react w/ acid
& base
- located on the right
side of the
table
Metalloids are elements that have some characteristics
of metals and some characteristics of nonmetals.
 Located between the metals and nonmetals on the
periodic table (near the stair-step line)
Differences in physical properties can be used to
separate mixtures.
To separate heterogeneous mixtures:
Filtration – a process that separates solids from liquids
by passing through filter paper.
ex/ making coffee uses a paper filter to separate the
coffee beans from the water.
To separate homogeneous mixtures (solutions):
Distillation – a process that uses differences in boiling
points to separate a mixture
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
Sketch a diagram of the distillation demo.
Label the names of the lab equipment used in
your drawing.
Write a brief description of the process of
distillation.
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