Group Tasks• Right Side:• I have developed a way to

make bottled water that I guarantee will be chemical free.

• Typically already, bottled water costs about $3/gallon.

• You need to determine how much I should charge for Dr. Joe’s Chemical Free Water.

• Left Side:• Recently, a disturbing report

was issued on the dangers of dihydrogen monoxide. The biggest concern in the report was that this chemical had been detected in a number of areas (like the air we breathe and different

places in our homes). • You need to determine what

you would do to protect yourself from this chemical. (http://www.dhmo.orghttp://www.dhmo.org) http://www.dhmo.org

What’s the deal?• In the first case, we’re assuming water is not a

chemical.

• In the second case, we’re being told it is a dangerous chemical.

• I ask you then, what is a chemical? Are all chemicals “bad” or harmful?

• Many people assume chemicals are bad

What is Chemistry?

• Study of matter and its changes.

• Matter is anything that takes up space and has mass.

• WOAH!! Isn’t that nearly everything?

• So chemistry plays a role in your everyday life, more than you probably know!

Balloons

• Why the differences?

• Because it’s different stuff in there, right?

• Yes, but, that’s not enough of an answer in science! We want to know why those particular “things or chemicals” did those different things.

Macroscopic vs Nanoscale

• What we saw happen we say occurred on a macroscopic level

• To really understand why it happened, we need to look at a level we can’t see with our naked eyes…a microscopic level

• Actually, we need to look at the behavior of atoms and molecules…this is called the nanoscale level

• Much of what we’ll do in here is attempt to explain what we see at a macroscopic level in terms of the nanoscale!!!

Properties of Matter

• Physical– Color– Mass– Volume– State (solid, liquid, gas)

During a physical change, the fundamental particles are not changed

During a chemical change, the fundamental particles are changed

•Chemical–it reacts with acid–it does not react with air

Density

• Amount of mass filling a volume

• Density = mass/volume

• Constant for a material (at a given Temp)

Using Density

• At a certain temperature, ethanol has a density of 0.80 g/mL. If I needed 150 g of ethanol, what volume of ethanol would I need to measure out?

150 g1 mL

0.80 g= 187.5 mL

Dalton’s Atomic TheoryDalton’s Atomic Theory

1. All matter is composed of indivisible atoms.

2. An element is a type of matter composed of only 1 type of atom.

3. A compound is a type of matter composed of atoms of two or more elements chemically combined in fixed proportions.

4. A chemical reaction is simply a rearrangement of the atoms present to give new chemical combinations.

– A physical changephysical change is a change that does not alter the identity of the matter.

– A chemical changechemical change is a change that does alter the identity of the matter.

– A compoundcompound is a pure substance that can be decomposed by a chemical change into simpler substances

– An elementelement is a pure substance which cannot be broken down into anything simpler by either physical or chemical means.

• Chemical Change: Sugar is a compound that can be easily decomposed to simpler substances by heating. One of the simpler substances is the black element carbon, which cannot be further decomposed by chemical or physical means.

• Physical Change: (H2O) As a solid, liquid, or gas still has only H2O water molecules present. The “H” and “O” are not broken apart going from ice, water, to steam. Only the energy per individual H2O molecules changes.

Ice Water Steam

Atom

Identifying an Atom

• Atoms of a particular element will all have same number of protons

• Z = atomic number• A = atomic mass number• Write Nuclide Symbols to Identify

AtomSymbolA

Z

Nuclide Symbols

• Write the nuclide symbol for an atom with mass number 15 and 8 neutrons.

An atom that has the same number of neutrons as isoC59

27

oC5727Ni59

28 uC6029 Fe58

26

Atomic Mass

1 Atomic Mass Unit = A.M.U. = amu

1 amu = mass of the proton = mass of the neutron

The Periodic Chart lists atomic mass underneath the atomic symbol

The Mole

number of atoms needed to have atomic mass in grams

6.02 x 1023

Using the Mole

• The link between macroscopic grams and nanoscale number of particles!

• If I had 0.750 mol of Pb,– How many grams of Pb must I have?– How many atoms of Pb must I have?

The Periodic Table

“Periodic Trends”

 

The Real Periodic Table

The Periodic Table

• Rows are periods• Columns are groups• “sections”

Main Group

Transition

Inner Transition

Metals

Nonmetals

Metalloids