Introduction To Chemistry A Motivational Lesson

CHEMISTRY ELEMENT, COMPOUND AND MIXTURE

Non-Metal Metal (l) (l) (s) (g) (s) (g) – gas (l) – liquid (s) - solid ELEMENT Non-Metal Metal (l) (l) (s) (g) (s) (g) – gas (l) – liquid (s) - solid

The periodic table Increasing metallic character Be B C N O F Ne Na Mg Al Si P S Cl Ar Increasing metallic character K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Metals Metalloids Nonmetals This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 2.0 UK: England & Wales License

What is an element ? Element A chemical substance Simplest substance Cannot be decomposed to a simpler substance Built up from one type of atoms only

Examples of Metals ( Sodium ) Na Use Sodium Lamp

What is a Compound ? 2 or more elements chemically combined with a chemical Bond between the particles

Compound Constituents : H , C , O Glucose Use : Carbohydrates Compound Constituents : H , C , O

Mixtures Homogeneous Mixture – composition and properties are uniform (sometimes called a solution) Air – principal components include O2, N2 & CO2 Vodka – principal components are EtOH & H2O Brass – solid solution of Cu and Zn Ruby – solid solution of Al2O3 and Cr2O3

Mixtures Heterogeneous Mixture – composition and properties are non-uniform Chocolate Chip Cookie – chocolate, sugar, dough, etc. Concrete – cement, sand, aggregate Vomit – Depends upon previous intake of food and drink

Air– Oxygen, Nitrogen, Carbon dioxide, water vapor etc. Examples of Mixtures Air– Oxygen, Nitrogen, Carbon dioxide, water vapor etc. Is it homo or hetero?

Components : Lactose, water, proteins, vitamins, minerals etc Milk Components : Lactose, water, proteins, vitamins, minerals etc Is it Home or hetero? Depends on how long it sits, it may separate into creamy curds and liquid whey

Changes in Matter Chemical Physical Gas Sublimation Evaporation Deposition Condensation Changes don’t have to be on a macro scale - at the very trace analysis scale can also get changes at ppb (109) and ppt (1012) level Melting Solid Liquid Freezing

Changes in Matter Physical change Substance changes physical appearance without altering its identity e.g. changes of state ice melting to form water

Changes in Matter Chemical changes (or chemical reactions) Substances transform into chemically different substances i.e. identity changes e.g. decomposition of water