Types of Chemical Bonds Ionic Bond – between a Metal and a Non-Metal (M + NM) *refer back to your ionsIn an ionic bond, electrons are lost or gained

Covalent Bond – between a Non-Metal and a Non-Metal (NM + NM)In a metallic bond, electrons are shared.

**Use your periodic table and Lewis Dot Diagrams to determine the type of bond.

Hydrogen and Oxygen are both non-metals, so this is a covalent bond. The chemical formula is H2O.To practice bonding and writing chemical formulas, use your yellow sheets from class.

Some Vocabulary you need to know:What is the difference between a compound, a mixture, and a solution?Compound:

Consists of atoms of two or more different elements bound together. Can be broken down into a simpler type of matter by chemical means. Has properties that are different from its original elements. Always contains the same ratio of atoms.

Mixture: Consists of atoms of two or more different elements and/or compounds physically intermingled. Can be separated into its original elements/compounds by physical means. Often retains many of the properties of its original elements.

Solution: A mixture that looks like a single substance. Has the same properties throughout. Contains a solute (substance that dissolves) and a solvent (substance into which the solute dissolves).

Examples:Compound: Mixtures: Air around you!

A chemical formula is an easy way to describe a chemical compound. It shows the elements that were combined and how many atoms are present.

A molecule is formed when two or more atoms join together chemically (O2 – this is a chemical formula). A compound is a molecule that contains at least two different elements (H2O – this is a chemical formula). *All compounds are molecules, but NOT ALL molecules are compounds! Once the elements chemically bond together, the properties of the compound are different than the properties of the individual elements.Remember Sir Dalton taught us that elements in a compound have a fixed ratio for the atoms. For example, H2O has two hydrogen atoms (the subscript tells us how many atoms are present for that element) and one oxygen atom. That means there will always be two hydrogen atoms combined with one oxygen atom (it doesn’t matter if you have 1 water molecule or 50). A coefficient is placed in front of a chemical formula and changes the number of atoms in the entire molecule/compound. (2H2O – changes the number of Hydrogen atoms to 4 and the oxygen atoms to 2.)

A chemical equation shows how compounds and elements react with one another. Remember – an element is a substance consisting of one kind of atom (Aluminum – Al). A compound is a substance that is made of more than one kind of atom (H2O or NaCl).

The Law of Conservation of Matter states that matter is neither created nor destroyed, so we must have the same number of atoms in the reactants (left hand side) that we do in the products (right hand side).

Here is the chemical equation for Photosynthesis – it “looks” different because it is BALANCED!! We will talk about balancing equations in the next unit!

REACTANTS yields PRODUCTS

How many atoms are in each compound?REACTANTS: PRODUCTS:6CO2 = 6 carbons and 12 oxygens C6H12O6 = 6 carbons 12 hydrogens, and 6 oxygens12H2O = 24 hydrogens and 12 oxygen 6H2O = 12 hydrogens and 6 oxygens

6O2 = 12 oxygensTotal Reactants: 6 carbons, 24 hydrogens, 24 oxygens Total Products: 6 carbons,24 hydrogens,24 oxygens