Basic ChemistryChapter 2

MATTER & ENERGY• Matter

• Anything that occupies space and can be weighed

• Chemistry examines the nature of matter

• Energy

• No mass

• Ability to do work

• Matter is the substance that is moved by energy

Matter

• Building blocks: solid, liquid, gas

• Physical change –nature of substance is unchanged

• Chemical change –nature of substance is changed

ENERGY

• No mass

• We measure the effect of energy on matter

• Two types: Kinetic and Potential

ENERGY• Forms:

• Chemical -stored within bonds, released as heat

• Electrical -movement of charged partials (e-)

• Mechanical -direct movement of matter

• Radiant -electromagnetic waves

• Energy is converted from one form to another, any not used is released as heat.

COMPOSITION OF MATTER

• Elements

• Atoms

• Protons (p+) –positive charge

• Neutrons(n0) –neutral or no charge

• Electrons (e-) –negative charge

• Opposites attract!

http://www.chemicalelements.com/

ELEMENTS OF THE HUMAN BODY

ATOMS

• Orbital Model –electron cloud

• Atomic number –number of protons

• Atomic mass –sum of all protons and neutrons

• Isotopes –vary in number of neutrons

• Radioisotopes –radioactivity, heavy isotopes

CHEMICAL BONDS & REACTIONS

• Molecules, Compounds, Reactions, OH MY!

• Molecules =same

• Compounds =different

• Reactions =associations or dissociations of atoms

• Bonds form between molecules and compounds

• Energy relationships

CHEMICAL BONDS• Bonds are energy relationships

• Opposites attract while “like” or same repels

• Role of electrons

• Occupy fixed regions called electron shells or energy levels

• Valence shell electrons participate in bonds

ENERGY LEVELS

ENERGY LEVELS

• Valence Shells (energy levels)

• Outer shell

• If fewer than 8 electrons will try to: share, gain, lose

ENERGY LEVELS

CHEMICAL BONDS• Ionic –one atom gains electron and second loses

• Covalent –electrons are shared between atoms

• Hydrogen –form bridge between two electrically negative atoms

CHEMICAL REACTIONS

• Synthesis –larger molecule formed

• Decomposition –larger molecule is degraded

• Exchange –synthesis and decomposition; switch

BIOCHEMISTRY

• Inorganic compounds do not contain carbon atoms

• Water, salts (electrolytes), acids and bases

• Organic compounds contain carbon atoms

• Carbohydrates, lipids, proteins and nucleic acids

INORGANIC COMPOUNDS

• Water –thermoregulatory, universal solvent, reactivity, cushioning, lubrication

• Salts –cations other than H+, electrolytes

• Acids –H+, proton donors

• Bases –OH-, proton acceptors

• pH –concentration of acid; [protons]

pH 7 =1 x 10-7 pH2 =1 x 10-2 pH12 =1 x 10-12

pH 7 =1 x 10-7=0.0000007pH6 =1 x 10-6 =0.000006pH1 =1 x 10-1 =0.1pH14 =1 x 10-14 =0.000000000000014

ORGANIC COMPOUNDS

• Large, complex molecules

• Functional groups are reactive parts

• Monomers combine to form polymers

• Carbohydrates, Lipids, Proteins, Nucleic Acids, ATP

CARBOHYDRATES

• “Hydrated Carbon”

• Monosaccharides are building blocks

• Disaccharides –double sugars

• Polysaccharides –branching chains

LIPIDS• More carbon & hydrogen than

oxygen

• Insoluble in water

• Saturated or unsaturated

• Triglycerides –fatty acids + glycerol

• Phospholipids –contain phosphorus

• Steroids –flat with interlocking rings

PROTEINS

• Amino acids are building blocks

• Amine + acid group + functional group (R)

• Most are complex in structure

Primary Secondary

Tertiary

PROTEINS

• Fibrous or Globular

• Function depends on shape

• Enzymes (end in –ase)

NUCLEIC ACIDS• Building blocks are nucleotides

• Code for genes

• 5 types: adenine, guanine, cytosine, thyamine, uracil

• Deoxyribonucleic Acid (DNA) & Ribonucleic Acid (RNA)

ADENOSINE TRIPHOSPHATE

• Chemical energy

• Adenine base + ribose sugar + 3 phosphates

• Phosphate bonds are high energy