Unit 3: Introduction to Chemistry What is chemistry?

What we will be learning over the next 6 weeks Before Christmas Break History of the Atomic Theory The Atom & It’s Subatomic Particles Reading Element Squares & The Periodic Table Determining number of subatomic particles Valence Electrons & The Bohr Model After Christmas Break Elements, Substances, Compounds, & Mixtures Physical & Chemical Changes Chemical Reactions How to Write Chemical Formulas Balancing Chemical Equations What we will be learning over the next 6 weeks

During notes, write the red info on the inside tab. Bellwork: Pick up handouts. Cut foldable out like the example. Fill in planner for the week. History of the Atomic Theory Prezi During notes, write the red info on the inside tab. Activity: Use your foldable to complete the timeline. TURN IT IN WHEN DONE.

Bellwork: Pick up notes & activity. Did you get your timeline turned in yesterday? Atom’s Family Challenge Powerpoint

The Atomic Theory states... Fill this in for Bellwork All matter is made up of atoms. All atoms of a given element are identical. Compounds are formed when atoms of different elements combine in fixed amounts. An atom cannot be created or destroyed, just rearranged in a chemical reaction.

Fill this chart in as we go through the notes. Charge Location Discovered By Proton Neutron Electron Atoms are known as the building block of matter. They are made of 3 subatomic particles...

Carbon atoms make up width of 1 strand of human hair. 1,000,000 Carbon atoms make up width of 1 strand of human hair. 1 trillion atoms to make one human cell 500 years Amt. of time it would take you to count the atoms in a grain of salt.

outside of the nucleus in electron orbits/levels Check your chart. Charge Location Discovered By Proton positive (+) inside the nucleus Rutherford Neutron no charge Chadwick Electron negative (-) outside of the nucleus in electron orbits/levels Thomson Atoms are known as the building block of matter. They are made of 3 subatomic particles...

Periodic Table- Arrangement of all chemical elements. Each element represents one atom of the given element. The table is arranged in order by increasing atomic number.

Atomic Number= # of protons= # of electrons Remember: APE Mass Number= # of protons + # of neutrons Remember: MAN

4 Steps to Determining the Number of Protons, Electrons, and Neutrons Look up the givens on the periodic table: atomic number & mass number (Hint: this is the decimal--round the number to a whole number) Fill in the number of protons and electrons (Hint: same as the atomic #) Mass #- atomic #= # of neutrons Check your math. A=P=E & the protons & neutrons should=mass # 4 Steps to Determining the Number of Protons, Electrons, and Neutrons

Bellwork: Pick up handouts. Grab scissors, glue, & map pencils. Have your notes on your desk. Start cutting.

History of The Periodic Table Originally proposed by Dmitri Mendeleev (1869) Grouped elements according to their atomic mass, as he did he noticed that families had similar chemical properties. Changes made by Henry Moseley (1914) Organized table by atomic number. –Columns then contained elements with similar properties This is what we follow today! History of The Periodic Table

Getting to Know The Families vs. Periods Families/Groups are the vertical columns (up & down). There are 18 families. They are grouped because they have similar properties & the same # of valence electrons. Periods are the horizontal rows (left to right). There are 7 periods. They are grouped because they have the same # of electron orbitals. They do not share similar properties Getting to Know The Families vs. Periods

Important Families to Know Periodic Table Song Alkali Metals Group 1A. Is the most reactive group. Always bonded with other elements. Elements: Li, Na, K, Rb, Cs, Fr Alkaline Earth Metals Group 2A. Never found freely in nature. Found in foods. Elements: Be, Mg, Ca, Ba Halogens Group 17/7A. The most active non-metals. Bond with alkali metals. Elements: F, Cl, Br, I Noble Gases Group 18/8A. Stable elements that exist on their own. (Small amts.) Elements: He, Ne, Ar, Kr, Xe

Take 5 minutes and see if you can answer these questions. Let me know when you are ready to check your answers.

Time to color! Cut out. Glue into the correct column. 5 minutes! Color the METALS some shade of GREEN! Color the METALLOIDS YELLOW! Color the NON-METALS some shade of pink. Time to color! Cut out. Glue into the correct column. 5 minutes!

Metals •Metals are good conductors of heat and electricity. •Metals are shiny. •Metals are ductile (can be stretched into thin wires). •Metals are malleable (can be pounded into thin sheets). •Metals are corrosive. (A chemical property of metal is its reaction with water) Metals

Non- Metals •Non-metals are poor conductors of heat and electricity. •Non-metals are not ductile or malleable. •Solid non-metals are brittle and break easily. •They are dull. •Many non-metals are gases. Non- Metals

•Metalloids (metal-like) have properties of both metals and non-metals. •They are solids that can be shiny or dull. •They conduct heat and electricity better than non- metals but not as well as metals. •They are ductile and malleable. Metalloids

# of Electrons Each Level Can Hold The electrons found in the outermost energy level used for bonding. The Bohr model shows the location of ALL electrons in the different energy levels. Valence Electrons # of Electrons Each Level Can Hold 1st Level 2 electrons 2nd Level 8 electrons 3rd Level