 Anything with And

The Gangsta

And

 The smallest unit of an element, having all the characteristics of that element

 A Nucleus composed of Protons – Positive charge Neutrons – Neutral or No charge  Electron shells which are made of Electrons – Negative charge

 No Charge or are Neutral!  The number of protons (+) is always equal to the number of electrons (-)

 They form COMPOUNDS  Hydrogen + Hydrogen + Oxygen chemically combine to form H2OH2O

 Hydrogen?  Oxygen?

 Water?  Compounds do not have the same properties as the elements they are made from

Compounds NOT Elements Pure Ag Pure Au

 Two Types of Bonds: Covalent and Ionic Bonds  Covalent Bonds – Involve two or more elements sharing electrons from the outer electron shell of an atom.

Atoms which are both nonmetals

 How they Work! How they Work!

 Carbon Dioxide = CO 2

 Ammonia = NH 3

 Ionic Bond which forms between a metal and a nonmetal

 Form when one atom loses an electron to become positively charged.

And a second atom gains the electron to become negatively charged.

 Losing or gaining an electron makes each particle more stable.  Since an atom is always neutral, these charged negative and positive particles are NOT atoms.  They are called IONS

 A positive ion is attracted to a negative ion creating an ionic compound held together with an ionic bond!  A good example of an ionic compound is

 How they work! How they work!

Compounds held together with covalent bonds

H2OH2O  The names of the elements in the compound  The amount of atoms or ions in the compound  A subscript refers ONLY to the atom (or ion) it immediately follows in the formula  If there is no subscript, there is one atom (or ion) of the element in the formula

H 2 OH 2 O 2 KHSO 3 CaCO 3 H 2 O 2 Which atoms/ions? How many of each atom/ion?

 Tells us how many particles (usually molecules) of the compound are in the formula. H 2 O = 1 water molecule 2H 2 O = 2 water molecules Coefficient Subscript

Glycine (an amino acid found in proteins) 4C 2 H 5 NO 2 How many molecules are in the formula? Which atoms are in the formula? How many of each atom? (Multiply the coefficient by the subscript!)

Now What? 1)Complete Worksheet with your group! 2)Is your group ready for a quiz on reading chemical formulas? 3)Everyone in your group will receive the same group grade made up of the average of all of your quiz scores!

a)3BiPO 4 b)2CH 2 O c)5CCl 4 d)4C 2 H 5 NO 2 d)3HC 6 H 7 O 6 e)4H 2 C 2 O 4 f)2KHSO 3 g)5Al 2 Cl 9 K 3 Is your group ready to take a quiz on reading chemical formulas?