CLASSIFYING MATTER

Vocabulary & People PureMixture CompoundMoleculeDiatomic HeterogeneousHomogeneous FormulaSubscriptCoefficient OUTCOME QUESTION(S): S How do you classify matter using the words: element, compound, atom, molecule, mixture and pure? S How do you use a formula to find the elements in the molecule and the number of atoms of each element?

Matter: Anything that has mass and takes up space, or volume.

Mixture Substance contains more than one kind of particle. Pure Every particle that makes up a substance is the SAME.

PURE 1. Elements Simplest form matter Smallest particle of an element - atom 2. Compounds Two or more elements chemically bonded Smallest particle of an compound – molecule A bucket of gold atoms (Au) and a bucket of water molecules (H 2 O) are both PURE since in both cases there is only ONE type of particle

Element: Sodium – all pure sodium atoms It’s possible to have compounds of the same atoms: Called diatomic (two atoms) molecules Oxygen gas – O 2 Hydrogen gas – H 2 Compound: Salt – all pure sodium chloride molecules

Homogeneous (can not see the pieces)  Mixture is evenly distributed – “solution”  Cannot physically separate different particles Salt and water Coke Cheese

Heterogeneous (can see the pieces) Mixture is not evenly distributed Different particles can be separated physically Sand and water Pizza Bubble tea

1000 kg Would the tree and the ash weigh the same?

Law of Conservation of Matter: In any chemical reaction matter cannot be created or destroyed. Atoms will rearrange to form new compounds, but the number and type of atoms will not change during the reaction

subscript Chemical Formula Shows type and amount of each atom present in a compound H O H H H O +

and 3 atoms of oxygen H2OH2O3 form 3 molecules of water. 6 atoms (3 x 2) of hydrogen H H O H H O H H O coefficient 1 The subscript “1” is never shown in the formula – it is invisible – since the element symbol is present it is assumed there is at least 1… Subscript: # of atoms (per element) in a compound Coefficient: # of total molecules present

Compound Coefficient Total of each element (Subscripts · Coefficients) KHCO 3 1K: 1 H: 1 C: 1 O: 3 3 AlCl 3 3Al: 1 · 3 = 3 Cl: 3 · 3 = 9 6 CBr 4 6C: 1 · 6 = 6 Br: 4 · 6 = 24 5 H 2 SO 4 5H: 2 · 5 = 10 S: 1 · 5 = 5 O: 4 · 5 = 20 4 C 11 H 22 O 12 4 C: 11 · 4 = 44 H: 22 · 4 = 88 O: 12 · 4 = 44

Mg(NO 3 ) 2 3 Mg O O O N O O O N Brackets: subscripts outside a bracket multiply by everything inside the bracket. Remember the subscript applies to what is directly in front of it 11 Mg: 1 · 3 = 3 N: 1 · 2 · 3 = 6 O: 3 · 2 · 3 = 18

Compound Coefficient Total of each element (Subscripts · Coefficients) 2 NaNO 3 2 Na: 1 · 2 = 2 N: 1 · 2 = 2 O: 3 · 2 = 6 2 Al(NO 3 ) 3 2 Al: 1 · 2 = 2 N: 1 · 3 · 2 = 6 O: 3 · 3 · 2 = 18 3 Ca(OH) 2 3 Ca: 1 · 3 = 3 N: 1 · 3 · 2 = 6 Br: 4 · 6 = 24 4 H 2 (SO 4 )4 H: 2 · 4 = 8 S: 1 · 1 · 4 = 5 O: 4 · 1 · 4 = 16

Vocabulary & People PureMixture CompoundMoleculeDiatomic HeterogeneousHomogeneous FormulaSubscriptCoefficient CAN YOU ANSWER THESE QUESTIONS? S How do you classify matter using the words: element, compound, atom, molecule, mixture and pure? S How do you use a formula to find the elements in the molecule and the number of atoms of each element?