What Are ElementsChapter 12 Lesson 1Pages E6 – E11
Objectives Understand that all matter is made
up of the same basic particles Recognize atoms as fundamental
particles of matter Identify the basic parts of an atom Identify an element as any type of
matter made up of only one kind of atom
Main IdeaAll matter is made up of elements. The smallest piece of an element is called an atom.
VOCABULARY
ELEMENTA substance that cannot be broken apart into other substances.
These are the building blocks of matter.
ATOMThe smallest particle of an element that still has the properties of that element.
ELECTRONSParticle in an atom that has a negative charge.
NUCLEUSCentral core of an atom
PROTONParticle in the nucleus of an atom that has a positive charge.
NEUTRONParticle in the nucleus of an atom that has NO charge.
MOLECULETwo or more atoms joined together by chemical bonds.
Elements Page E6 All matter is made up of
elements. Some substances (like diamonds)
are made from a single element Most substances are made from 2
+ elements
Atoms Page E6 The smallest part of an element Can only be seen by special
microscopes Ancient Greek philosophers were
the first to suggest all matter is made of atoms.
1897 - ThomsonBall of positive
charged has negatively charged electrons located throughout.
1911 - RutherfordSmall, dense nucleus
surrounded by mostly empty space. Electrons move in that space.
1913 - BohrElectrons travel in
specific orbits around the nucleus.
1926 - SchrodingerElectrons clouds or orbitals
show the probability of finding an electron in a particular location.
Organization of AtomsElectrons have very little
mass. The nucleus accounts for most of the mass.
The nucleus is made up of protons and neutrons
Organization of Atoms Protons have a positive charge,
electrons have a negative charge, and neutrons have no charge.
Coal, graphite, and diamonds are all carbon, differing in the way their atoms are arranged.
Graphite Atoms are arranged in sheets the
separate easily.
Diamond The hardest natural
substance found on Earth.
Atoms packed tightly together with each atom bonded to four other atoms.
This gives diamonds their hardness
Coal Anthracite coal
contains 90 to 98 percent pure carbon
Important fossil fuel formed from dead plants
Elements Alone and Joined An elements properties come
from the atoms that compose it. Atoms can join together through
chemical bonds to form molecules
Molecules can contain atoms of the same element or atoms of different elements.
QuestionWhat are the tiny particles
that make up an atom?
AnswerElectronsProtonsNeutrons
QuestionHow do atoms, molecules,
and elements differ?
AnswerAtoms are the smallest
particles of an element. Molecules are two or more
atoms joined together. Elements are the building
blocks of all matter
QuestionWhy do the different forms of
carbon have different properties?
AnswerBecause their atoms are
arranged differently.