Atoms and Elements and Compounds: Are they Related? HRMS 7th Grade

Matter Matter is anything that has mass and volume (takes up space).

ATOMS ALL MATTER IS MADE OF ATOMS Definition: ATOMS ARE THE SMALLEST PIECE OF MATTER and CANNOT BE BROKEN DOWN INTO A SIMPLER SUBSTANCE.

ATOMS HAVE 3 BASIC PARTS (Subatomic Particles) PROTONS NEUTRONS ELECTRONS

PROTONS (POSITIVE CHARGE) ARE FOUND IN THE NUCLEUS AND MAKE UP MOST OF THE MASS OF THE ATOM. VERY IMPORTANT!!! The number of protons an atom has tells you what kind of atom it is!!!!

NEUTRONS (NO CHARGE) ARE FOUND IN THE NUCLEUS MAKE UP PART OF THE MASS OF THE ATOM

Isotopes Atoms of the same element that have a different number of neutrons. EX: Carbon Carbon-12 Carbon-13 Carbon-14

Isotopes & Radioactive Decay Atoms are most stable when they have the same number of Pro/Neu in the nucleus… So, having more neutrons causes atom to be unstable & “repulsion” builds up. Nucleus becomes more stable when the extra particles are released & energy is given off. RD is the release of extra nuclear particles & energy.

ELECTRONS (NEGATIVE CHARGE - ) FOUND IN THE ELECTRON SHELL (cloud) ORBITING THE NUCLEUS. TAKES UP MOST OF THE SPACE IN AN ATOM.

Valence Electrons Outermost electron(s) in the cloud/shell 8 is the magic number!!!!!! (octet rule)

Ions Atom where the total number of electrons does not equal the total number of protons (atom will have a pos or neg charge) Cation= pos (loss of e-) Anion=neg (gain of e-) EX: Fe2+, Al3+, O2-

How to Find: # of Protons The atomic number IS the number of protons Atomic number is located on the periodic table

# of Protons If the atomic # is 7, what is the # of protons? If an atom has 22 protons, what is its atomic #. How many protons does Oxygen have? What is Oxygen’s atomic #? Neon has 10 protons. What is its atomic #? If an atom has 35 protons, what is the name of the atom?

How to Find: # of Neutrons atomic mass - # of protons = # of neutrons You can find the number of neutrons by subtracting the atomic mass from the # of protons (atomic number). atomic mass - # of protons = # of neutrons

# of Neutrons If an atom’s mass is 9amu and has 4 protons, how many neutrons does it have? If an atom’s mass is 14amu and has atomic number of 7, how many neutrons does it have? How many neutrons does aluminum have? How many neutrons does calcium have? An atom has a mass of 28amu and 14 neutrons, what type of atom is it?

# of Neutrons If an atom of germanium has 41 neutrons and 32 protons, what is its atomic mass? Nickel has an atomic number of 28 and has 31 neutrons, what is its mass?

Isotopes & Mass Number If we have a different number of neutrons, will the mass be affected? EX: since C-14 has 8 neutrons, the mass number is 14amu instead of 12amu (C-12).

Isotopes Atoms of the same element that have a different number of neutrons. EX: Carbon Carbon-12 Carbon-13 Carbon-14

How to Find The # of electrons IS EQUAL to the # of protons

# of Electrons If Helium has 2 protons, how many electrons does it have? If the atomic number of magnesium is 12, how many electrons does it have? If an atom has 21 electrons, what type of atom is it?

How to Find: Atomic Mass You can find the atomic mass by adding the # of protons and the # of neutrons # of protons + # of neutrons = atomic mass

Putting it all together… Element Atomic # Atomic Mass Proton Neutron Electron Au 79 118 Cr 52 24 B 11 5

Discovery of the Atom (pg. 80) By the early 1800’s, John Dalton proposed that all substances are made up of atoms. In 1898, J.J. Thomson, proposed that atoms are made up of smaller parts. In 1911, Ernest Rutherford, proposed that atoms have electrons and a positively charged nucleus.

Dalton’s Atomic Theory All matter is made of atoms. Atoms are indivisible and indestructible. 2) All atoms of a given element are identical in mass and properties 3) Compounds are formed by a combination of two or more different kinds of atoms. 4) A chemical reaction is a rearrangement of atoms.

Niels Bohr’s model of the atom that shows the electrons revolving around the nucleus in circular paths called orbits.

Electron Cloud Model Current Atomic Theory: Electrons travel in regions of various thicknesses called clouds (shells).

Label the atom below on your packet! What type of atom is this? How do you know?

PIN THE NUCLEUS ON THE ATOM

Elemental Candy

ELEMENTS ARE PURE SUBSTANCES MADE OF TWO OR MORE OF THE SAME KIND OF ATOM. SOME COMMON ELEMENTS HYDROGEN (H), HELIUM (He), OXYGEN (0), Notice that the first letter is capital and the next letter is lower case.

ELEMENTS ARE THE BUILDING BLOCKS OF MATTER. CANNOT BE BROKEN DOWN INTO A SIMPLER SUBSTANCE. HAVE THEIR OWN UNIQUE SET OF PROPERTIES THAT NO OTHER ELEMENT HAS.

ELEMENTS There are 92 naturally occurring elements on the periodic table. This means they are in nature and not made in a laboratory by scientists. As of the year 2015 there are 118 known elements but there are gaps.

Elements Most Elements are rarely found alone in nature react with water or oxygen easily undergo a chemical change

Atoms and Elements Activity As a group, look at the food labels on the items at your table. Make a list of the items in the left hand side column and in the right hand side column make a list of any elements found in that substance. You may use your periodic table to help you identify the elements.

The food item would be: Cooked Ham What are the elements that are found on this food label?

QUESTIONS???? What are the most commonly occurring elements in the food labels? What items seemed to have the most amount of elements in them? Can you predict what that means about the food item? Why do you think the baby formula has such a variety of elements? Can you predict what the other items on the food label are if they are not elements?

PERIODIC PATTERNS

Periodic Table The periodic table is an organized table of each element. Each box gives information about each type of element found on Earth.

Dmitri Mendeleev (1869) In 1869 Mendeleev and Lothar Meyer (Germany) published nearly identical classification schemes for elements known to date. The periodic table is base on the similarity of properties and reactivities exhibited by certain elements. Later, Henri Moseley ( England,1887-1915) established that each elements has a unique atomic number, which is how the current periodic table is organized. http://www.chem.msu.su/eng/misc/mendeleev/welcome.html

ELEMENTS ARE ORGANIZED IN THE PERIODIC TABLE ACCORDING TO INCREASING ATOMIC NUMBER.

ELEMENTS ARE ORGANIZED IN THE PERIODIC TABLE OF ELEMENTS ACCORDING TO THEIR SIMILAR CHARACTERISTICS

Elements & their symbols Iron- Fe (Ferrum) Lead- Pb (Plumbum) Elements & their symbols SOME COMMON ELEMENTS HYDROGEN (H), HELIUM (He), OXYGEN (0), Notice that the first letter is capital and the next letter is lower case. Gold- Au (Aurum)

Element Info in Each Box Atomic Mass Atomic Number Symbol Name

Arrangement of the Periodic table Periods – Rows are called periods. The elements in these rows change conductivity and number of electrons as you move across the table. Groups – Columns are called groups or families. These elements have the same properties because of the number of electrons.

How is the Periodic Table Organized? Periods Even though they skip some squares in between, all of the rows go left to right. When you look at a periodic table, each of the rows is considered to be a different period

There are 7 periods. Each period represents the number of electron shells. Elements in period 1 have 1 electron shell. Elements in period 5 will have 5 electron shells.

Across the Periodic Table Periods: Are arranged horizontally across the periodic table (rows 1-7) These elements have the same number of valence shells. 2nd Period 6th Period

When a column goes from top to bottom, it's called a group or family. Groups Groups are often called families because these elements seem to be related. **Elements in the same group show similarities in their chemical and physical properties.

There are 8 main groups across the periodic table There are 8 main groups across the periodic table. Groups or families have the same number of electrons in the outermost shell. The group number tells you how many electrons are in the outermost shell. Group 1 has 1 electron in outermost shell. Group 4 will have 4 electrons in outermost shell.

Down the Periodic Table Family: Are arranged vertically down the periodic table (columns or group, 1- 18 or 1-8 A,B) These elements have the same number electrons in the outer most shells, the valence shell. Alkali Family: 1 e- in the valence shell Halogen Family: 7 e- in the valence shell

Reading the Periodic Table: Classification Nonmetals, Metals, Metalloids, Noble gases

Periodic Table: Metallic arrangement Layout of the Periodic Table: Metals vs. nonmetals Nonmetals Metals

Infamous Families of the Periodic Table Notable families of the Periodic Table and some important members: Alkali Alkaline (earth) Transition Metals Noble Gas Halogen Chalcogens

Alkali Group -Group #1 -1 valence electron in outer shell -very reactive with water & other elements -low densities & melting points

Alkaline Earth Group -Group #2 -2 valence electrons in outer shell -very reactive but not as much as alkali -denser, harder & higher melting points

Transition Metals -Groups 3-12 -Valence electrons vary -Usually found combined with other elements -higher melting points, good conductors

Halogen Group -Group #17 -7 valence electrons in outer shell -most combined to make salts (salt formers) -most are non-metals

Noble Gas Group -Group # 18 -8 valence electrons in outer shell (the happy gases! ) -NOT REACTIVE

Periodic Table: Metallic arrangement Layout of the Periodic Table: Metals vs. nonmetals Nonmetals Metals

Elements are classified: *Metals *Nonmetals *Metalloids The Periodic Table Of Elements Elements are classified: *Metals *Nonmetals *Metalloids Xenon Scandium

Properties of a metal *Malleable - flattened *Good conductors – conducts heat or electricity *Malleable - flattened *Ductile – can be made into wires *Shiny- you can see you reflection Gold Iron Magnesium

Properties of a Nonmetal *Not malleable – cannot be flattened *Not shiny *Poor conductors Chlorine Helium Bromine

Silicon Arsenic Properties of Metalloids Semiconductors – Average conductors Shiny but brittle Silicon Arsenic Boron

Periodic Table: Metallic arrangement Layout of the Periodic Table: Metals vs. nonmetals Nonmetals Metals

Sulfur GOLD (AU) Silver

ELEMENTS IN OUR BODIES IODINE

1.Oxygen (65%) 2.Carbon (18%) 3.Hydrogen (10%) 4.Nitrogen (3%) 5.Calcium (1.5%) 6.Phosphorus (1.0%) 7.Potassium (0.35%) 8.Sulfur (0.25%) 9.Sodium (0.15%) 10.Magnesium (0.05%) 11.Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%) 12.Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts) 99% of the mass of the human body is made up of only six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Every organic molecule contains carbon. Since 65-90% of each body cell consists of water (by weight), it isn't surprising that oxygen and hydrogen are major components of the body

Elements in the body Oxygen Carbon Hydrogen Nitrogen Calcium Phosphorus Potassium Sodium Chlorine Magnesium Sulfur

GASES FLUORINE KRYPTON NITROGEN NEON

Atoms to Elements to ???

ELEMENTS & COMPOUNDS ARE THE BASIC BUILDING BLOCKS OF MATTER EACH ELEMENT & COMPOUND HAS SPECIFIC PROPERTIES