Atoms, Elements and How They Behave Basic Chemistry Atoms, Elements and How They Behave

_______ ___________  ____________ ______  ________  _______  Start Small End Big _______ ___________  ____________ ______  ________  _______  _______________  ___________

ATOM: ______________ of an element that still has the __________ of that element. Made up of: - ____________________, p+, Charge of __ - _________, e-, charge of __ - _________, n, charge of ___

Structure of an Atom e Orbit: N P Nucleus: P N e

Orbits spin and rotate in three dimensions. Structure of an Atom P N e Orbits spin and rotate in three dimensions.

Orbits spin and rotate in three dimensions. Structure of an Atom Orbits spin and rotate in three dimensions.

Each Orbit is a ______ _______from the nucleus. Structure of an Atom P N e Each Orbit is a ______ _______from the nucleus.

Structure of an Atom P N e

Structure of an Atom

Each type of atom has its own number of ________ Structure of an Atom - e Each type of atom has its own number of ________ N + P + P N - - e

The different combination of p+, n and e- make each element _______ Structure of an Atom - e The different combination of p+, n and e- make each element _______ N + P + P N - - e

Structure of an Atom Normally, all the “+” of the protons and the “-” from the electrons balance out and the overall charge of the atom is zero. We call this a ________ atom.

What if an atom loses an electron? Structure of an Atom - What if an atom loses an electron? e e N N + P P + P P N N - e -

Structure of an Atom What if an atom gains an electron? - + + - - e N P + P N - e - - - e

Any charged atom is called an ___ Structure of an Atom Any charged atom is called an ___ - Positive ions are called _______ - Negative ions are called ______

The Periodic Chart Atomic number _____ __________________ Atomic Mass _______ __________________ Assume _______= ________ (except ions)

Atomic Mass = Protons + Neutrons Why don’t the electrons figure in?

Drawing Atoms: Each orbit can hold a maximum number of electrons. You must fill the inner orbits before adding electrons to the outer orbits.

Examples e e 12 Mg 24 e P N

Examples Sodium: 11 Na 23 29 Cu 63

Valence electrons Electrons in __________ orbit Atoms want a ________ outer orbit They will bond with atoms that fill the orbit

Examples Look at the column number on periodic table to figure out Valence electrons Na __________ Cl ____________

Examples Look at the column number on periodic table to figure out Valence electrons C __________ N____________

Main Elements in Human Body Oxygen Carbon Hydrogen Nitrogen

Compounds Two or more atoms ______ together in a _________________ H20 vs. H2O2 what is different?

Compounds Parts are _____________ together ___________ proportions required Properties of a compound are __________ from the properties of the elements that make up that compound.

Mixtures Mixtures have “ingredients” that do _______ chemically with each other Each ingredient keeps its ____ ____________________ Definite proportions ___________ 3 Types: ________, __________, __________

Mixtures Solution: _______________ (even throughout) _______ (dissolved substance) completely dissolves in __________ (liquid) ________________ Doesn’t _________ Example - ___________________

Mixtures Suspension: _______________ May look homogeneous if shaken but particles will __________ ____________ (murky) Can be ______________ Example: _________________

Mixtures Colloid: _____________ BUT does not settle Sort of ____________the other two. Appears ____________ (let light through but image is not sharp) Does not filter out. Example -

What are three big differences between Mixtures and Compounds? Mixtures vs. Compounds Look at your notes: What are three big differences between Mixtures and Compounds?

Types of bonds that form Compounds Ionic Bond- ____________ _______________________

Creates ____________ that holds atoms together IONIC: Creates ____________ that holds atoms together

Types of bonds that form Compounds Covalent- each atom ______ ___________ with the other

Change in the arrangement of atoms that creates a different substance Chemical Reactions Change in the arrangement of atoms that creates a different substance A + B  C synthesis reaction A  B + C decomposition A + B  C + D Displacement

Chemical Reactions Reactants: Products: A + B  C _________ ________

Al + O2  Al2O3 C2H6 + O2  CO2 + H2O H20  H+ + OH- Chemical Reactions Al + O2  Al2O3 C2H6 + O2  CO2 + H2O H20  H+ + OH-

Properties of Water Water is held together with special covalent bond called _____ covalent bond - Means water has poles, or ends. - O is the __________ end - H’s are the ________ ends

Properties of Water

Properties of Water Cohesion: __________________ ___________________________

Cohesion Creates __________________ - allows stickbugs to walk on water!

Adhesion Glass stirring rod

Water is the Universal Solvent Anything with a charge will attract water molecules and dissolve Ionic and polar molecules have __________ ______________(like fat) do not have charge and will not dissolve

Acids and Bases Acids: HX (in water)  H+ + X-

Properties of Acids Taste sour – think of lemon Turn litmus paper from blue to red Corrodes Metal Examples:_____________ _______________________

Acids and Bases Base: XOH (in water)  OH- + X+

Properties of Bases Taste bitter – cough meds. Turn litmus paper back to blue after acid turns it red Can cause serious burns Examples:

Acids and Bases - Examples NaOH + H2O  Na+ + ___ + H2O HCl + H2O  ___ + Cl- + H2O

Acids and Bases will “cancel” each other out When an Acid and a Base are mixed together they will ___________each other and create ______ and a _____ This is a ___________ Reaction

Neutralization Reaction HCl + NaOH  NaCl + H2O _____ ____ HNO3 + KOH  KNO3 +H2O _____ _____

pH = ___________________ Concept of pH pH = ___________________ A way of measuring how many Hydrogen ions, H+, there are in a solution Determines whether a solution is an __________________

pH Scale – a measure of the concentration of Hydrogen Ions Acid Neutral (water) Base 1 2 3 4 5 6 7 8 9 10 11 12 13 14 High H+ Low OH- High OH- Low H+ H+ = OH-

pH must stay between _____ in the human body Concept of pH Where is the “safe” pH? pH must stay between _____ in the human body Another factor that must maintain homeostasis

Intestines are _______ ________ are necessary Concept of pH Are there exceptions? Stomach is _______ Intestines are _______ ________ are necessary weak acids or bases that react with strong acids or bases to prevent sudden changes in pH

What is the pH of Rain water?? Usually between _________ - Water reacts with CO2 in air to form Carbonic Acid (H2CO3)

What is the pH of Rain water?? Acid Rain: - Rain water reacts with pollutants such as Sulphur dioxide and Nitrogen oxides in air - Forms Sulphuric Acid, Nitric Acid, Ammonium Sulphate - ______________________