Chapter 2: Antacids
Introductory Activity – Part 1
Fill a film canister about half-full with room temperature water. Place about a quarter of a tablet of Alka-Seltzer ® in the canister and quickly push the top on. Stand back and observe. This is called an “Alka-Seltzer ® cannon.”
In your lab group, brainstorm all of the chemistry involved in this process. What chemistry would you need to learn about to understand what’s happening? Share your brainstorming with the class.
Introductory Activity – Part 2
List everything you know about acids and bases. Where have you used them or come in contact with them in your life? Explain what you understand about antacids. Share your ideas with the class.
Section 2.1—Types of Matter
Matter can be classified
Matter
Pure Substances
Mixtures
Element CompoundHomogeneous
(Solutions)Heterogeneous
Matter
Anything that has mass and takes up space
Anything made from atomsExamples:
MoleculesCellsPeopleAirWater
Pure Substances versus Mixtures
MixturesPure Substances
Every piece of matter is the same
More than one type of matter mixed
together
Matter is classified as either a pure substance or a mixture
Elements versus Compounds
CompoundElements
Every atom is the same type of atom
More than one type of atom chemically bonded together. Every molecule is
the same.
Pure substances are either elements or compounds
Elements
Pure substanceEvery atom is the same
Elements can be found on the periodic table!
Element
Single AtomCannot be separated by chemical or physical processes
Compounds
Pure substanceEvery molecule is the same
Compound
Single Molecule
Made of more than one type of atom bonded together
Can be separated by chemical reactions only
Mixtures
HeterogeneousHomogeneous (aka “solution”)
It looks the same throughout
Different matter can be seen (chunks, bubbles, floaties,
layers, etc.)
Mixtures can be classified as homogeneous or heterogeneous
Mixtures
Not a pure substancePhysical combination of more than 1 type of pure substance
Mixture
>1 different type of matter
Can be separated chemically or physically
Mixture possibilities
Mixtures can be any combination of solids, liquids and gases:Solid-solid: Medicine tabletSolid-gas: Pop Rocks candySolid-liquid: Ice waterLiquid-liquid: Lemon waterGas-Liquid: Carbonated waterGas-Gas: Air
True solutions, Colloids & Suspensions
ColloidTrue Solution
Particles don’t settle out and are
too small to scatter light
Particles don’t settle out but are large enough to
scatter light
Suspension
Particles will settle out over time
Dissolved Particle Size Increases
Particles Scattering Light
If the dissolved particles are large enough to scatter light, we say it exhibits the “Tyndall Effect”
SolutionLight passes through unchanged
Colloids exhibit the Tyndall EffectLight is scattered by larger solute particles
Connect these concepts with Antacids
What type of matter do you think antacids are?Pure substance (Element or compound)Mixture (homogeneous or heterogeneous)
Connect these concepts with Antacids
Antacids are mixtures.They contain active & inactive ingredientsWhat purposes could the inactive
ingredients serve?
Connect these concepts with Antacids
Inactive ingredients mightAdd enough volume to make the pill able to be
handeledAdd colorAdd flavorAllow the tablet to be compressed and formed
Let’s Practice
Tin foilExample:Determine if
each is element,
compound, homogeneous
or heterogeneous
mixtures
Copper pipe
Concrete
Carbon tetrachloride
Sports drink
Let’s Practice
ElementTin foilExample:Determine if
each is element,
compound, homogeneous
or heterogeneous
mixtures
ElementCopper pipe
Heterogeneous mixConcrete
CompoundCarbon tetrachloride
Homogenous mixSports drink