Mixtures & Solutions
Investigation 1
Separating Mixtures
Part 1 – Making & Separating Mixtures
Vocabulary
• Mixture – a substance containing two or more
materials with different properties.
• Property – a characteristic of an object (something you
can observe)
– Size, shape, color
• Solution – a special mixture formed when a material
dissolves in another.
• Dissolving – a process in which one material disperses
uniformly into another material so that the first
material seems to disappear.
– Two materials mixed evenly together
Part 1 – Making & Separating Mixtures
Main Ideas/Content
• Water and solid material make a mixture.
• Some mixtures can be separated by hand or with
filters (ex: M & Ms, coins, water and gravel)
• A mixture can be any combination of a solid,
liquid, or gas.
– Solid and solid – bronze (copper and tin), steel (carbon
and iron)
– Solid and liquid – vegetable soup, cereal & milk
– Gas and gas – air
– Gas and liquid – soda, seltzer water
Part 2 – Separating a Salt Solution
Vocabulary
• Solvent – a substance that dissolves a solute to form a
solution (ex: water).
• Solute – a substance that dissolves in a solvent to form
a solution (ex: salt, iced tea crystals, detergent).
• Evaporate – to turn into a gas, like water into water
vapor.
• Element – a substance that cannot be broken down
any further.
• Atom – the smallest particle of an element. Atoms are
the building blocks of matter.
Part 2 – Separating a Salt Solution
Main Ideas/Content
• A solution is a special kind of mixture in which
one of more materials dissolve in another (ex:
salt water).
– Solutions can be separated using evaporation
• Almost everything on Earth is a mixture of two or
more substances, except for elements.
– There are 92 naturally occurring elements on Earth
– Elements are arranged on the periodic table from
lightest to heaviest.
Part 3 – Observing Crystals
Vocabulary
• Crystal - the solid form of a material that can be
identified by its properties, such as shape, color,
and pattern.
• Evaporation – causes liquids to dry up; the liquid
turns into gas and disperses into the air.
Part 3 – Observing Crystals
Main Ideas/Content
• When a solution evaporates, it leaves the
dissolved solid material behind.
• The salt crystal is a square with an X from corner
to corner.
• Salt is made up of the elements sodium (Na) and
chlorine (Cl).
– A substance made up of more than one element is a
compound.
Part 4 – Separating a Dry Mixture
Main Ideas/Content
(FOSS Science Stories – Earth Elements)
• Humans are made up of 75% water.
• Five elements make up most of the human body (and
most other organisms)
– Oxygen, carbon, hydrogen, nitrogen, calcium
• Earth is made up of only a few main elements as well
– Iron, oxygen, silicon, magnesium, nickel, sulfur
• Although Earth and everything on it come from only
a few elements, those elements combine in a huge
variety of ways to create many different materials.
Famous Scientists from Investigation 1
(From FOSS Science Stories)
• Humphry Davy – discovered way to separate salt into
sodium and chlorine.
• Henry Cavendish – famous for his study of the
composition of air; first person to isolate hydrogen
from air.
• Robert Boyle – “father of chemistry”; conducted
many experiments with gases.
• Marie Curie –discovered the elements radium and
polonium; conducted research on radioactivity; won
the Nobel prize twice.