Transcript homogeneous mixture

Physical Science
Do Now
February 17th 2011
Today we will be discussing the differences
between Heterogeneous and Homogeneous
mixtures. Copy the following:
The words Heterogeneous and Homogeneous
have Latin pre-fixes, which mean –
Hetero – Different
Homo – Same
SWBAT define the difference between a
heterogeneous mixture and a homogeneous mixture
Homework Review
• State the relationship between atoms and
elements. Are both atoms and elements matter?
– An atom is the smallest unit of an element that has
that element’s properties. Both atoms and elements
are matter.
• List two types of pure substances:
– Elements
– Compounds
• Describe matter, and explain why light is not
matter. Is light made of atoms and elements?
– Matter has mass and takes up space. Light has no
mass or volume and no atoms.
• Define molecule, and give examples of a
molecule formed by one element and a
molecule formed by two elements
– A molecule is the smallest unit of a substance
that keeps all physical and chemical properties of
a substance. Oxygen (O2) is an example of a
molecule formed by one element. Water (H20) is
a molecule formed by two elements.
• Classify each of the following as an element or
compound:
– A. Sulfur (S8)
• Element
– B. Methane (CH4)
• Compound
– C. Carbon monoxide (CO)
• Element
– D. Cobalt (Co)
• Compound
• State the chemical formula for water.
– Water has 2 hydrogen and 1 oxygen atom = H2O
• Compare and contrast mixtures and pure
substances, give an example of each.
– A pure substance has the same composition
throughout.
– A mixture has more than one pure substance.
Mixtures
• Most matter in the
universe is found in
mixtures.
• A mixture is made from
two or more
substances either
elements, compounds
or both - that are not
chemically combined.
Mixtures and
compounds differ in
two ways…
Substances in a mixture keep their individual
properties.
Parts of a mixture are not necessarily present
in specific ratios.
Compound
• A compound has properties different than the
elements that make it up.
• The parts of a compound are present in
specific ratio’s.
+
=
Hydrogen (g)
Water – H20 (l)
Other Compounds
Compounds and Mixtures
• Most of the matter around you is in the form
of compounds or mixtures.
• Water, carbon dioxide, salt, vinegar, baking
soda, lye, sugar, gasoline, and bleach are all
chemical compounds.
Heterogeneous Mixture
• A mixture in which different materials can be
easily distinguished.
• Examples: Pizza, trail mix, beach sand, bird
seed, oil & water, dirt
Solutions
• Homogeneous mixture: is a substance in which
two or more substances are uniformly spread out.
• Solution is another term for homogeneous mixture.
• Examples: Salt water, gasoline, vinegar, hand lotion
Miscible VS. Immiscible
• Miscible – when two liquids are mixed together and
they are evenly spread.
– Gasoline
• Immiscible – when two liquids do not mix together
– Oil & water
Today’s Assignments
• Classwork
– Mixture Worksheet
– We will spend approximately 5-7 minutes per
section then review it and move on!
• Homework
– “Science and the Consumer”
– Page 43
– Read and answer both questions in notebook
Classwork Review
1. Identify each of the following samples of
matter as: homogeneous matter or
heterogeneous matter
• (a) spaghetti sauce - heterogeneous
• (b) table sugar - homogeneous
• (c) cough syrup - homogeneous
• (d) glass - homogeneous
• (e) river water - heterogeneous
• (f) nitrogen - homogeneous
• 2. Classify each of the following as: element (ele) or
compound (com) or mixture (mix)
• (a) spaghetti sauce - Mixture
• (b) table sugar - Compound
• (c) cough syrup - Mixture
• (d) silver - Element (Ag)
• (e) orange juice - Mixture (Water & Oranges)
• (f) iced tea - Mixture
• (g) glass - Mixture
• (h) river water - Mixture
• (i) nitrogen - Element (N)
• (j) Phosporous - Element (P)
• (k) oxygen - Element (O)
• (l) air - Mixture
• 3. Choose words from the following list to fill in the blanks
in the sentences.
• mixture
heterogeneous matter
substance
• compound homogeneous matter
element
• (a) Matter that has uniform characteristics throughout is
called HOMOGENEOUS MATTER
• (b) Matter that has parts with different characteristics is
called HETEROGENEOUS MATTER
• (c) A simple substance that cannot be broken down into other
substances by chemical means is called a(n) ELEMENT
• (d) A chemical combination of simple substances is called a
COMPOUND
• (e) A physical combination of different substances that retain
their individual properties is called a(n) MIXTURE
• (f) Either an element or a compound may be referred to as a
SUBSTANCE
Part 4
• "The components of a mixture can be separated
by physical means; a compound must be
chemically broken apart into its components. A
mixture has a variable composition; a compound
has a definite composition."
• 5. Classify these samples of matter as a:
substance / homogeneous mixture /
heterogeneous mixture
• (a) copper - Substance
• (b) ink - homogeneous mixture
• (c) glue - homogeneous mixture
• (d) carbon mixed with sand- heterogeneous
mixture
• (e) water containing dissolved salt –
homogeneous mixture
• (f) flower – heterogeneous mixture
• (g) oxygen dissolved in water – homogeneous
mixture
• (h) apple juice – homogeneous mixture
• 6. Classify each of the following as a:
element / compound / homogeneous mixture /
heterogeneous mixture
• (a) water - compound
• (b) air - homogeneous mixture
• (c) sugar dissolved in water - homogeneous mixture
• (d) granite - - heterogeneous mixture
• (e) sand in water - heterogeneous mixture
• (f) peanut butter - heterogeneous mixture
• (g) carbon - element
• (h) table salt - compound
• (i) homogenized milk - homogeneous mixture
• (j) oxygen - element
• (k) blood - heterogeneous mixture
• (l) motor oil - homogeneous mixture
• 7. Fill in the blanks with:
• element / compound / homogeneous mixture / heterogeneous
mixture
• (a) Steel contains mostly iron plus trace amounts of at least one
other element. You could have heard of various kinds of steel,
stainless steel, cobalt steel, tungsten steel. Since the composition
of steel can vary, it is a homogeneous mixture.
• (b) Hydrogen is listed on the periodic table. It is a Element.
• (c) Milk is a homogeneous mixture because it consists of more
than one component, and its composition varies. For example,
you have probably seen whole milk, 2% milk, and non-fat milk at
the grocery store. These three grades of milk all differ in their fat
content.
• (d) Table salt is composed of the elements sodium (Na) and
Chlorine (Cl) in fixed proportions. It is a compound.
• (e) Seawater contains sodium chloride and many dissolved
minerals. The composition of seawater changes from place to
place. Some seawater is high in dissolved minerals, but in other
regions the seawater is lower in minerals. Since its composition is
variable, seawater must be a homogeneous mixture.