Download The Chemistry of Life

The Chemistry of Life
Elements, Atoms, and
Properties
What does Chemistry have to do with
Biology?

Living things are made up of simple elements
as well as complex carbon compounds.

If we begin to understand how these
elements interact we can better understand
how the body works.
Property of Matter

What is matter?
–

Matter: anything that takes up space.
Three States/Phases of matter:
–
–
–
Gas
Liquid
Solid
Types of Properties

Physical Properties:
–

Anything that has a mass, volume, and weight
Chemical Properties:
–
Describes a substances ability to change into
another substance as a result of a chemical
change.
Physical Properties

Solids have three main properties:
–
It has a definite weight.

–
It has a definite mass.

–
Measure of force of gravity on an object
Quantity of matter in an object
It has a definite volume.

Amount of space an object takes up
Physical Properties

Other physical properties
–
–

Color, shape, odor, texture, taste, and hardiness
Melting point, Boiling point.
Physical Properties can be:
–
Observed and Measured WITHOUT permanently
changing the identity of matter.
Physical properties are the
things we know about objects
using our senses.
sight
hearing
taste
touch
smell
Bear
ribbon
ball
book
bottles pineapple
Properties of
Solid objects
flexible
rigid
smooth
rough
soft
hard
colored
pointed
flat
transparent
opaque
Did you have other answers? Can you support your choice?
Chemical properties

Ability of a substance to change into another
new substance as a result of a chemical
change.

Chemical Change:
–
–
Process by which a substance is permanently
altered.
Often difficult if not IMPOSSIBLE to reverse
effects.
Phases of Matter

Phases: states that an object may undergo
–
Solid, Liquid, and Gas. (Physical Properties)
Composition of Matter

Atoms: from greek word atomos
–
Meaning “uncut”
 Building
Block of ALL Matter!!!
Atomic Structure

Nucleus: center most dense part of the atom.
–

Holds protons and neutrons.
What are protons, neutrons, and electrons?
Protons and Neutrons in Nucleus


Protons (Positive
charged particle)
Neutrons (Neutral
charge)
Electrons

Negative charged molecules
Energy Levels

Where the electrons are.
Atomic Mass and Mass number

Atomic number:
–

number of protons in
the nucleus of an
atom.
Mass number:
–
total number of
protons and
neutrons.
Chemical Elements

Substances, known as elements, consist
entirely of one element

Element:
–
one of over 109 different substances found in
nature or created by man.
Atoms

Atoms contain equal numbers of electrons
and protons
–
–
Gives no charge= happy
Example


Hydrogen = 1 proton and 1 electron
If a atom has a charge that means that it has
more electrons if negative or more protons if
it is positive.
Calculating # of protons, electrons and
neutrons.

For any element:
–
–
–

Number of Protons = Atomic Number
Number of Electrons = Number of Protons = Atomic Number
Number of Neutrons = Mass Number - Atomic Number
For krypton:
–
–
–
Number of Protons = Atomic Number = 36
Number of Electrons = Number of Protons = Atomic Number
= 36
Number of Neutrons = Mass Number - Atomic Number = 84
- 36 = 48
Website Game

http://education.jlab.org/elementmath/index.h
tml
Isotopes

Atoms of the same Element with the same number of
protons but different number of neutrons.

For Example: Carbon
–
–

This is useful for scientists because some can be
more reactive or unstable
–

Normal = 6 neutrons
Can have 7 or 8 neutrons
This means they are very easy to break bonds causing
radiation
Said to be radioactive
Compounds and Bonding

Chemical Compounds:
–
–
Combination of 2 or more different atoms with
different properties.
When elements combine to form substances,


Consisting of 2 or more different atoms, chemical
compounds are produced.
Example: Water H20
Interactions of Matter

Chemical Bonding:
–
–
Combining of elements involving interactions
In order to achieve stability, an atom will either
gain, lose, or share electrons.
Bonds

Ionic Bonds

Covalent Bonds
Ionic Bond

Ion: charged particle

Ionic Bond: involves transfer of electrons
Covalent Bonds

Chemical bond formed by sharing of
electrons.

Molecule: combination of atoms that are held
together by covalent bonds
–
–
Have no overall charge
Example: sugars, fats, proteins, water
Chemical Reactions

Chemical Reactions:
–
Process by which a chemical change occurs
–
Chemists have learned that most important
factors in determining whether a reaction will
occur is the flow of energy.
Mixtures and Solutions

Mixture:
–

A combination of substances in which the
individual components retain their own properties.
Solution:
–
A mixture in which one or more substances
(solutes) are distributed evenly in another
substance.(solvent)
Acid and Bases


Depends on pH.
What is pH?
–
A measure of how acidic or basic something is?


Acid:
–

Scale ranges 0-14.
Any substance with a pH below 7.
Base:
–
Any substance with a pH above 7
Acid

Forms Hydrogen Ions: H+ in WATER.

When compound HCl, hydrogen chloride is
added to water.
–
–
The H+ and the Cl- form HCl
H+ and Cl- form Hydrochloride in water.
Base

Forms hydroxide (OH-) ions in water.

Sodium hydroxide (NaOH) is dissolved in
water, it forms sodium ions (Na+) and
hydroxide (OH-).

The Solution has an abundance of OH- ions
which creates a pH above 7.