Molecule Notes pg 64tial Questions: What are the basic differences of elements, molecules, and compounds? What determines the number of molecules in a chemical equation?

From really small to really big…. You could start really small... - Subatomic particles of matter   - Atoms     - Molecules       - Macromolecules         - Cell organelles           - Cells             - Tissues               - Organs                 - Systems                   - Organisms                     - Populations                       - Ecosystems                         - Biomes                           - Planets                             - Systems with Stars                               - Galaxies                                 - The Universe                                   ...And finish really big.  © KeslerScience.com

Atoms Lets Review – Atoms are the basic building blocks of matter. Objects that take up space and have mass are called matter. Everything around you is made up of matter. Atoms are made from subatomic particles called  protons (+)(which carry a positive electrical charge) neutrons (which carry no electrical charge) electrons (-) (which carry a negative electrical charge). The protons and neutrons cluster together in the central part of the atom, called the nucleus, and the electrons are found at different energy levels in an electron cloud. © KeslerScience.com

Elements Lets Review – A particular atom will have the same number of protons and electrons and most atoms have at least as many neutrons as protons. An element is a substance that is made entirely from one type of atom. For example, the element hydrogen is made from atoms containing just one proton and one electron. If you had very, very good eyes and could look at the atoms in a sample of hydrogen, you would notice that most of the atoms have no neutrons, some of them have one neutron and a few of them have two neutrons. These different versions of hydrogen are called isotopes. All isotopes of a particular element have the same number of protons, but can have different numbers of neutrons. If you change the number of protons an atom has, you change the type of element it is. If you change the number of neutrons an atom has, you make an isotope of that element. All known elements are arranged on a chart called the Periodic Table of Elements. © KeslerScience.com

Mixture A mixture is a substance made by combining two or more different materials in such a way that no chemical reaction occurs. A mixture can usually be separated back into its original components. Some examples of mixtures are a tossed salad, salt water and a mixed bag of M&M's candy. © KeslerScience.com

Molecules Molecules Examples of molecules O2 – oxygen Molecules are a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound Made up of two or more atoms The atoms can be the same or different. Examples of molecules O2 – oxygen O3 - ozone molecule H2O – water CO2 - carbon dioxide H2SO4 – sulfuric acid © KeslerScience.com

Molecules Oxygen atoms Needs 2 electrons to have a full outer shell 6 valence electrons in an oxygen atom Molecules Formed when two or more atoms bond together chemically Elements can bond with the same atoms or different atoms. These bonds form as a result of the sharing or exchange of valence electrons among atoms. Valence electrons are the electrons on the outermost energy level. Oxygen molecule O2 Valence electrons are always looking to fill the outer most electron layer. By sharing electrons both oxygen atoms now have complete outer shells. Two oxygen atoms bonding by sharing electrons © KeslerScience.com

NaCl Compound Compounds Elements A compound is a chemical substance formed when two or more different elements bond in a specific proportion. The elements lose their individual chemical properties and the compound has new properties. Poisonous gas Explosive solid NaCl Compound © KeslerScience.com

Compounds Compound Chemical bonds are a result of the sharing or exchanging electrons among the atoms. There are two types of bonding: ionic bonding, where an electron from one atom is transferred to another atom. You wind up creating two ions as one atom loses an electron and one gains one. covalent bonding, where electrons are actually shared between two or more atoms in a cloud. The smallest unbreakable unit of a compound is called a molecule. 2 Hydrogen atoms 1 Oxygen atom Water Molecule © KeslerScience.com

H2O H +H + O Chemical Formula Chemical Formulas The recipe for a chemical substance Tells the number of atoms of each element in a compound or molecule Uses symbols for the elements present and subscripts (small numbers) to indicate the number of elements Ex. H2O - water H2O H +H + O subscript H H O 2 Hydrogen atoms and 1 oxygen atom © KeslerScience.com

2H2 + O2 → 2H2O Chemical Equation Chemical Equations A shorthand that scientists use to describe a chemical reaction The number in front of the element symbol (called a coefficient) indicates the number of molecules. If no coefficient appears in front of a molecule, we interpret this as meaning one. Coefficient 2H2 + O2 → 2H2O 2 hydrogen molecules + 1 oxygen molecules = 2 water molecules © KeslerScience.com

Quick INB Action – Molecules Practice folder pg 65 Element Molecules Compounds 1. Quickly sketch the 3 circles 2. Draw each object in the correct circle. © KeslerScience.com

Quick Action – Molecules Practice Grab a partner and let’s practice. Is it a molecule or a compound? Formula Molecule Compound Element Both Compound and Molecule O2 NaCl CH4 H2 H https://www.youtube.com/watch?v=VOQzWLeZoEc Atoms elements and compounds This would be a good short video to show at this time. Write a rule that you can follow for determining the difference in a compound and a molecule? Here is a hint… All ___________ can be ___________, but….. © KeslerScience.com

Quick Action – Molecules Practice Grab a partner and let’s practice. Count the molecules in each balanced equation. 1. CH4 + 2O2 CO2 + 2H20 _____ CH4 _______ O2 _______ CO2 _________H20 2. 2Fe +3Cl2 2FeCl3 _____ Fe _____ Cl2 _____ FeCl3 3. P4O10 + H2O 4H3PO4 _____ P4O10 ______ H2O _____ H3PO4 © KeslerScience.com

Check for Understanding Can You- Describe the differences in an element, a molecule, and a compound? Determine the number of molecules in a balanced equation? Clear up any confusion and answer questions. © KeslerScience.com

Assessment folder pg 66 What are the basic building blocks for all matter? What do we call a substance consisting of a single type of atom? What is the difference between a molecule and a compound? What are valence electrons? When compounds are formed what happens to the properties? What is the smallest unbreakable unit of a compound? What is like a recipe for a chemical substance? What is the part of the formula that tells the number of atoms of each element? In a chemical equation, the number of molecules participating in the reaction? In the chemical equation: 2H2 + 2O = 2H2O How many Hydrogen atoms are there? How many Hydrogen molecules are there? How many oxygen atoms are there? How many water molecules are there? © KeslerScience.com