The Magic that Makes Chemistry The Magic that Makes Chemistry HappenHappen

Pb(NOPb(NO33))22 + 2KI 2KNO + 2KI 2KNO33 + PbI + PbI22

Pb(NOPb(NO33))22 + 2KI 2KNO + 2KI 2KNO33 + PbI + PbI22

Chemical Equation Chemical Equation

Chemical symbols showing what Chemical symbols showing what reactants and products take part in a reactants and products take part in a chemical reaction.chemical reaction.

ReactantsReactants are to the left of the arrow are to the left of the arrowProductsProducts are to the right of the arrow are to the right of the arrow

Pb(NOPb(NO33))22 + 2KI 2KNO+ 2KI 2KNO33 + PbI + PbI22

CompoundCompound

Made of two or more elements chemically combined. It can be broken down into simpler parts by a chemical reaction..

One compound is a moleculeOne compound is a molecule

One molecule of water HOne molecule of water H22OO One molecule of Lead Nitrate One molecule of Lead Nitrate Pb(NOPb(NO33))22

Pb(NOPb(NO33))22 + + 2KI2KI 2KNO 2KNO33 + PbI + PbI22

2 molecules of water would be…..2H2 molecules of water would be…..2H22OO

2 molecules of potassium iodide woud be..2 molecules of potassium iodide woud be..

2KI2KI

Elements are symbolized by one or Elements are symbolized by one or two letterstwo letters

Pb(NO(NO3))2 + 2K + 2KI 2 2KNO3 + + PbI2

K = Potassium N = Nitrogen O = Oxygen Pb = Lead I = Iodine Each time you see the symbol for an element, it

represents one atom of that element.

Pb(NOPb(NO33))22 + 2KI 2+ 2KI 2KKNNOO33 + PbI + PbI22

ElementElement

A substance that can NOT be broken down by A substance that can NOT be broken down by either physical or chemical meanseither physical or chemical means

Elements make compoundsElements make compounds

An atom is the smallest piece of an elementAn atom is the smallest piece of an element

All Elements can be found on the All Elements can be found on the Periodic Table of ElementsPeriodic Table of Elements

More on that laterMore on that later

MORE ON THAT LATERMORE ON THAT LATER

When the letters that symbolize the When the letters that symbolize the elements making up a compound elements making up a compound are written together they make a are written together they make a

formula

HH20 = the formula for water0 = the formula for water

HH2002 = the formula for hydrogen peroxide = the formula for hydrogen peroxide

CaClCaCl2 = the formula for calcium chloride = the formula for calcium chloride

TheThe formula represents one molecule of represents one molecule of the compoundthe compound

Subscript numbers are small are small numbers just to the right of the numbers just to the right of the letter of an elementletter of an element’s symbol’s symbol

HH2OO

The subscript number tells how many of The subscript number tells how many of that element are in the moleculethat element are in the molecule

If no subscript number is present, then If no subscript number is present, then there is one of that elementthere is one of that element

Full size numbersFull size numbers to the left of a to the left of a formula tell how many molecules of formula tell how many molecules of

a compound there area compound there are

22KNOKNO3

This formula indicates 2 molecules of potassium nitrate

In each of the two molecules of potassium nitrate there is:

1 potassium (K) 1 Nitrogen (N) 3 Oxygen (O)

How many atoms of each element are there in 2 molecules of potassium nitrate?????

CHEMICAL CHANGECHEMICAL CHANGE

When a CHEMICAL CHANGE happens, When a CHEMICAL CHANGE happens, the elements are rearranged during a the elements are rearranged during a chemical reaction and new compounds are chemical reaction and new compounds are formed. formed.

A brand new substance has been createdA brand new substance has been created