Block 3 & 4Dalton’s Atomic Theory & Rounding

Warm-Up

• Pick up handouts & put away cell phones!

• Finish collecting the lab data. WEAR YOUR LAB GOGGLES!• If you’re done start working on your conclusion.

Warm-up

• Pick up handouts & put away cell phones!

• On a sheet of paper under the warm-up section of your binder answer the following in complete sentences!• Title: Theory of the Atom • The first idea of the atom was brought about in

400 BC. Write an entry to the Roman Philosophers Committee on your theory of the atom.

Instrumentation & Measurement

• The more divisions of measurement the more EXACT we can be. • The more decimals

(or significant figures) the more exact a measurement is• When is it important

to have exact measurements?

How can we increase precision? • Increasing the numbers of significant digits!• Significant digit- all numbers in a measurement plus

an extra for estimation.

6.63 mL6.60 mL

Take Away• Accuracy- how close a measured value is to an

accepted value

• Precision- how close a series of measurements are to one another

Practice: The known mass of Cobalt is 58.93 g/mol• 58.9, 58.92, 59.0• 50, 51, 45• 62, 62.1, 62.0

Not accurate or precise

Precise but not Accurate

Both accurate & precise

Learning Check

• On a quarter sheet of paper write your name & period• Title: Learning Check- METRIC

• Answer the following on your own1. What instrument do we use to measure volume? 2. Write BOTH conversion factors for how many mm

in a cm3. ______ Hg in 43.2 cg

ATOMIC THEORY FOLDABLE

•With the paper horizontal, fold two flaps of equal size inward• Vertically fold paper into

thirds. Open back up.• Cut along the horizontal folds

on the FRONT FLAPS ONLY

Roots of Atomic Theory• Democritus• 1st proposed idea matter was no infinitely divisible• Matter made of particles called atomos• Atoms cannot be created, destroyed, or further divided• Different atoms have different sizes and shapes

Aristotle• Empty space cannot exist• Matter is made of earth, fire, and water

Atomic Theory Postulates

• It took 2,000 years to disprove Aristotle’s idea of nature.• Postulate- a thing suggested or assumed as true,

existent, or fact as a basis for reasoning, discussion, or belief

• Revise your warm-up idea or expand it based on the previous philosopher’s concepts.

John Dalton• Sept 6th 1766 – July 27th 1844

• First job age 10• Became a teacher at 12• Proficient in Latin by 14

• Meteorology, Color Blindness, & Hiking• Atomic Theory from studying gasses in 1803

All matter consists of a large number of tiny

particles• Matter• Anything that has mass and takes up space

• Atom• smallest particle of an element that retains the

properties of the element

Atoms of an element are unique, indestructible, and indivisible

• Element- pure substance that cannot be broken down into simpler substances

• Each element has its own characteristics• Atoms cannot destroyed or

divided • Smallest unit of matter

Atoms of a given element are identical in size, mass, and chemical properties

• Mass• measure that reflects the amount of

matter

• Chemical property• ability or inability of a substance to

combine with or change into one or more new substances

Chemical rxn involve separating, combining, or rearranging of atoms

• Atoms are neither created, destroyed, divided into parts, or converted into atoms of another element

• Chemical reaction (rxn)• Process by which the atoms of one or more substances

are rearranged to form different substances• Indicated by change in temperature, color, odor, and

physical state

Block 4• Phones away! I’m going to make sure there are 4 in

every box!

• Turn in your metric one step worksheet & work to the black trays

• WARM-UP: On page 11 of your packet, complete the chart on Dalton’s Postulates as best you can. Try not to use your foldable!

Homework Content• Learning Sapling Due

Thurs 11:00 pm• Content Quiz Next

Block!

• Pg 11- Review Dalton’s Postulates #1-5

• Dalton’s Postulates• Rounding Numbers• Metric One-Step

Conversions

Language of Chemistry (LoC) List 1

x2 The “2” is a subscript (s) solid. written after a chemical formula

x2 The “2” is a superscript (l) liquid. written after a chemical formula

2x The “2” is a coefficient (g) gas. written after a chemical formula

→ “yield”; shows a chemical reaction took place

(aq) aqueous. written after the formula for a chemical dissolved in water.

Chemical formula A2B, element symbols and subscripts

Chemical equation 2A + B → A2B, chemical formulas, a yield sign, and coefficients (usually)

Element Quiz Remediation

• On the back of your quiz write the elements you got wrong 3 times each

• Name, Symbol, Name, Symbol, Name, Symbol• IN A STRAIGHT LINE

• We always go by the spelling on the periodic table

TRADE & GRADE HMWK

• DO NOT grade your own paper.

• Write you name NEATLY on the right side of the page• IF I find a mistake or you “grade nicely” not only will

I regrade that person’s paper, but I’ll take the same points off your paper!

ROUNDING NUMBERS!

Packet Pg 4

Classifying Matter

• Using your notes & the textbook, define the three types of matter discussed in Dalton’s atomic theory on PG 11 of your packet

• Element

• Compound

• Mixture

Element Vs. Compound

• Elements are PURE SUBSTANCES found on the periodic table

• Compounds are two or more elements chemically bonded together

Diatomic Molecules

• Two of the same element bonded together is called a diatomic Element• They are unstable being alone and must bond to

themselves

• Br I N Cl H O F

Mixtures• Two or more different substances that are not

chemically combined and can be separated through physical means

• Heterogeneous mixtures- does not have uniform composition; can see different substances

• Homogeneous mixtures- uniform composition and a single phase; also called a solution

Let’s Practice Pg 13

LAB ACTIVITY

• You will find samples at each lab station• You must do each of the following for every sample:• Label by Table Number• Write a short qualitative description• Determine if it is a element, compound, or mixture

• Total of 12 Samples! • There can be more than 1 think in each container

In your groups

• Look at the labels I’ve handed you and the descriptions you made with a partner

• What table(s) would you place your description at?

• Have one person at your table go place your labels next to the sample you believe it is

Homework Content• Learning Sapling Due

Thurs 11:00 pm• Content Quiz Next

Block!

• Pg 11- Review Dalton’s Postulates #1-5

• Dalton’s Postulates• Rounding Numbers• Metric One-Step

Conversions

Metric REVIEW

SHOWDOWN• The Captain of your team is the person with the

next birthday. • You will write your answer on the board and keep it

to yourself. • Once everyone has had a chance to answer your

captain will say “showdown”• Everyone should compare answers. Talk about any

differences and come to a conclusion. • If you get the question correct you get a point.

Captians keep tabs on the points!

Write the conversion fraction for how many centigrams in a gram.

What is the conversion factor for how many millimeters are in a meter

Conversion Factor for kiloliters in a liter

How many cg is 56.7 gSHOW YOUR WORK

If the next town is 96 km away how far do I have to drive in meters? Show all work

A fat cat masses 23,004 mg. how fat is the cat in g?

How many sigfigs did the mass of the fat cat have? 23,004 mg

What is the estimated digit for a volume reading of 56.89 mL?

What is the estimated digit for a volume reading of 56.89 mL?Draw the instrument used to take this reading. BE SURE to mark the proper measurement lines!

If a flame burned for 450 milliseconds, how fast did it burn in Dekaseconds? Make sure you go to the base unit! (TWO STEP CONVERSION!!)