BIOLOGY NOTES BIOLOGY &

BIOCHEMISTRY PART 2PAGES 36-39

Standards___ Interpret formula representations of

molecules and compounds in terms of composition and structure

Essential Question1.

1.4

Why are carbon based molecules the foundation of life?

I. MatterMatter = anything that occupies _____ and

has _____.

List three different types of matter…

spacemass

A. The Structure of Matter

1. Atoms = the basic units of ________

• Atoms can be broken down into smaller parts called ____________ particles

a. proton = subatomic particle that has a ________ charge

matter

subatomic

positive

nucleus = the center of the ______ where protons and neutrons are located

c. electron = subatomic particle that has a ________ charge

electrons are in constant ________ around the _________ in an area known as the electron cloud

atom

negative

motionnucleus

b. neutron = subatomic article that has ____ charge

no

The electron cloud has different ________ levels that can hold a specific number of electrons

1st level (closest to the nucleus) =

______ electrons

2nd level = ______ electrons

2

8

energy

electron

neutron

proton

2. Elements

Element = a pure substance that consists

entirely of _______ type of atom

• elements cannot be _______ down into simpler substances

• each element is represented by a _______ symbol

1

broken

chemical

Oxygen = ___

Sodium = ___

Chlorine = ___

Sulfur = ___

Hydrogen = ___

Carbon = ___

Potassium = ___

Magnesium = ___

Calcium = ___

Phosphorus = ___

Nitrogen = ___

Iron = ___

ONa

ClS

H

C

K

Mg

CaP

N

Fe

• Of the naturally occurring elements, only about 25 are essential to ______.

• Of these 25, four ___, ___, ___, and ___ make up 96% of the mass of a human and are essential for life.

• The rest of the elements are present in very _______ amounts.

life

C H O N

small

1. Atomic Number = the number of _________ in an element.

• This is the element’s __________ because no two elements have the same amount of protons.

e.g.

protons

fingerprint

C = 6, N= 7, O = 8, etc.

II. The Combination of Matter

A. Compounds

Compound = a substance formed by the

________ combination of ___ or more

elements.

e.g.

chemical 2

NaCl (salt)H2O (water)C6H12O6 (glucose)

• chemical formula = a shorthand method of writing compositions of ___________

e.g. salt = NaCl water = H2O

• subscript = in chemical formulas, the small _______ next to the element that tells how many ______ of that element are in the compound

e.g. H2O = 1 atom O, 2 atoms H

C6H12O6 = 6 atoms C, 12 atoms H, 6 atoms O

numberatoms

compounds

How many atoms of each element are there in…..

C7O3H2 =

C57H110O6 =

7 atoms carbon, 3 atoms oxygen,2 atoms hydrogen

57 atoms carbon,110 atoms hydrogen,6 atoms oxygen

C7N4O2H9 =

CO2CaNa =

7 atoms carbon,4 atoms nitrogen,2 atoms oxygen,9 atoms hydrogen

1 atom carbon,2 atoms oxygen,1 atom calcium,1 atom sodium

B. Chemical Bonds – the formation of compounds

Elements will only combine to form

compounds when they become more

______ by forming a compound

• Atoms of different elements become more stable when they have ______ electrons in their outer ___________

stable

eightenergy level

(valence shell = outer energy level)

1. Types of Chemical Bonds

a. Ionic Bond = a chemical bond formed between two ______ when one or more _________ are transferred between the atoms resulting in atoms of _________ charge which are attracted to each other

e.g.

atomselectrons

opposite

salt

b. Covalent Bond = a chemical bond

formed between two _____ when they

share two or more _________

e.g.

atomselectrons

water, carbohydrates, & fats

• molecule = the structure that results when atoms are joined by _________ bonds

molecules make up most of the compounds found in ______ things

superscript = in chemical formulas, the large number found in ________ of compounds that tells how many ___________ of that compound exist

e.g.

covalent

living

front

molecules

2H20 = 2 molecules of water(4 atoms of Hydrogen, 2 atoms of Oxygen)

How many molecules? vs. How many atoms?

5C10O4H4 =

3C12H13ON =

5 molecules of polyestervs.

50 atoms carbon,20 atoms oxygen,

20 atoms hydrogen

3 molecules of bug sprayvs.

36 atoms of carbon39 atoms of hydrogen

3 atoms of oxygen3 atoms of nitrogen