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