Basic Chemistry

Chemistry:

• Chemistry is the science of matter.

– Scientists study chemicals, their properties, and REACTIONS (rxn).

• BIOCHEMISTRY is the chemistry of living things.

Water:

• most chemical rxns occur only in water (universal solvent)

• 90% or more of cells is H2O

• essential to life• Solutions are made up of the

–Solute:–Solvent:

Elements• most simple substance of

matter

• cannot be broken down

• ex. Fe. O, Mg, Na

Valence Electrons:

• outermost electrons

• (carry negative charge)

• responsible for bonding

• goal: to have a full valence energy level

Boxes on the Periodic Table

• Each box on the PT contains the following information:–Atomic number =

–Atomic Mass =

–Atomic Symbol =

–# of protons =

–#of neutrons =

–# of electrons =

6

C12.001

Compound

• Chemically bonding of 2 or more elements formed by:

1. Ionic Bonds:

2. Covalent Bonds

3. Polar Bonds

4. Hydrogen Bonds

Ionic Bond:–transfer of valence e-

–Forms between a metal and a nonmetal

–Ex. KI Potassium Iodide

Covalent bond:–Forms between 2 nonmetals

–Ex. CO = Carbon Monoxide

–Equal Sharing of Valence electrons

Polar Bonds • between covalent and

ionic bonds

• unequal sharing of the valence electrons

• have slightly positive and slightly negative ends

• Ex. Water!!

Adhesion and Cohesion • Water is attracted to other water.

–This is called cohesion.

• Water can also be attracted to other materials. –This is called adhesion.

                     

Surface Tension• the cohesion of water molecules

at the surface of a body of water

Capillary Action

• Capillary action however, is related to the adhesive properties of water.

• water molecules are attracted to the straw molecules.

Hydrogen Bonds :

–Weaker bonds than ionic and covalent

–Allow for large biological molecules•Ex. Proteins

•DNA

–Bonds water molecules together

Acid and Bases:

• Are ionized

• Can conduct electrical current

• Located throughout the body–Ex. Mouth, stomach

Acid :

Acids:

• Have extra H+ ions

• Have a sour taste

• Have a low pH (between 1 – 5)

Bases:

Bases:

• Have OH- ions

• Have a slippery feel

• Have a high pH (b/w 8-12)

pH Scale:

• Based on the # of H ion present

Buffers:• keep its pH constant • resist changes in pH when acids

or bases are added to them.

• In the body proteins act as a buffer, ex. Blood

Neutralization:

• Combing an Acids with a base

• results is neither an acid or a base.

• H+ form the acid and the OH- form the base combine to form water

• Ex. HCl + NaOH NaCl +H2O acid + base salt + water

Acid , Base Indicators:

• Phenolphthalein (base only)• pH paper (both)• Universal Indicator Solution

(Both)• Litmus paper (either)

–Red–Blue

Litmus paper:

pH paper:

Universal Indicator Solution:

Phenolphthalein:

Clear in the presence of an acid

Pink in a base

Inorganic chemistry:

• compound usually does not contain carbon or hydrogen

Organic Chemistry: • the compounds usually found in Living

or once living things

• contains carbon and hydrogen

• most common elements in living things are:

• C, H, O, N, P

• Carbon is often referred to as the element of LIFE

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