Download Do Now - March [4-2], 2009 - stroh

Do Now - March [4-2], 2009
Unscramble the following words and tell
which atomic theorist belongs to each
word(s).
1. MUPL DINPDUG
2. DEOCHTA ARY BETU
3. LUECNUS
4. OSMTOA
5. TURLENA OTREUNSN
Agenda
• Do Now/Announcements
• What is an element? an atom? a
compound?
• Atomic parts (protons, neutrons, and
electrons)
• Atomic Math!
• Work time: Individual and Group
• Exit Ticket
Objectives
• SWBAT define atom, element, and
compound
• SWBAT locate and describe the three
subatomic particles
• SWBAT do Atomic Math!
What is an ELEMENT?
• An element is a pure substance that
cannot be broken down into simpler
substances by physical or chemical
means
– An element is made of only one type of
atom
Add to Vocabulary Log!
Where are elements found?
• 91 occur on Earth naturally
– Examples: COPPER (#29), OXYGEN
(#16), GOLD (#79)
• Some have been developed by
scientists in labs
– Examples: RUTHERFORDIUM (#104),
CURIUM (#96), EINSTEINIUM (#99)
How are elements
organized?
Elements are organized on the
periodic table of the elements
We will learn more about the
organization of the periodic table
tomorrow!
Why do we use element
symbols?
• Each element has a unique chemical
name and symbol
– Symbols consist of one, two, or three letters
– First letter is ALWAYS CAPITALIZED
– Remaining letters are ALWAYS LOWER
CASE
• These names and symbols are universally
accepted by scientists to make
communication easier
What is an ATOM?
• An atom is the smallest particle of an
element that has all the properties of
that element
– Electrically neutral (no charge)
– Spherically shaped (like a ball)
– Composed of protons, neutrons, and
electrons
Add to Vocabulary Log!
How small is an ATOM?
• An atom is very small!
• In 2000, the world’s population was six billion
• By comparison, a copper penny contains
almost 5 billion times as many atoms of
copper!
World population
Atoms in a penny
000
6 000 000 000
29 000 000 000 000 000 000
What makes atoms different
from one another?
• There are about 110 elements
• That means there are 110 different
atoms
• Different atoms have different
numbers of subatomic particles
(protons, neutrons, and electrons)
Atomic Parts
(aka Subatomic Particles)
Protons
Neutrons
Electrons
PROTONS
(positive purple)
• Where are they found?
–IN THE NUCLEUS
• Mass
–1.6726 x 10-27 kg
• Charge
–1+ (positive one)
NEUTRONS
(no color, no charge)
• Where are they found?
–IN THE NUCLEUS
• Mass
–1.6749 x 10-27 kg
• Charge
–0 or neutral (no charge)
ELECTRONS
(in the red)
• Where are they found?
–OUTSIDE THE NUCLEUS
–Travel in SPECIFIC PATHS
1,839 ELECTRONS
• Mass
would equal the
-31
–9.1094 x 10 kg mass of ONE
NEUTRON!
• Charge
Electrons virtually
–1- (negative one) have NO MASS!
Review of Subatomic Particles
Subatomic
Particle
Protons
Location
IN NUCLEUS
Mass
1.6726 x 10-27
Charge
POSITIVE
kg
Neutrons
IN NUCLEUS
1.6749 x 10-27
kg
Electrons
OUTSIDE
NUCLEUS
9.1094 x 10-31
kg
NO CHARGE
(NEUTRAL)
NEGATIVE
Atomic Math!
•Atomic math helps us identify and
calculate….
number of protons
This helps number of neutrons
us
distinguish number of electrons
atoms
atomic number
from each
other!
atomic mass
ATOMIC NUMBER
• Atomic number is the number of
protons in an atom
• Atomic number determines the
element’s identity and position on the
periodic table
• Atomic number is the smaller number
in each element box on the periodic
table; is also the whole number (not a
decimal)
ATOMIC NUMBER
• Atoms are electrically neutral, so…
–The number of protons must
equal the number of…..?
–ELECTRONS!
ATOMIC NUMBER =
NUMBER OF PROTONS =
NUMBER OF ELECTRONS
ATOMIC NUMBER
Atomic Number Practice
1. What elements have the following
atomic numbers?
A) 27
B) 105
C) 4
2. What are the atomic numbers of the
following elements?
A) Pt
B) F
C) Te
ATOMIC NUMBER Practice
How many protons?
How many electrons?
ATOMIC MASS
• Atomic mass is the mass of the
nucleus (atom)
• Atomic mass = protons + neutrons
• Atomic mass is bigger number in each
element box on the periodic table
ATOMIC MASS
Atomic Mass Practice
In Atomic Math, use whole
numbers and round correctly!
1. If an element has 13 protons and 14
neutrons, what is its mass? What
element is this?
2. If an element has a mass of 89 and 39
protons, how many neutrons does it
have? What element is this?
What is ATOMIC MASS?
How many protons?
How many neutrons?
Practice Time!
1. Write the elements that have the following
atomic numbers.
A) 7
B) 14
C) 56
D) 84
E) 101
2. What are the atomic numbers for the
following elements?
A) chlorine B) helium C) tin D) iodine
3. How many protons, neutrons, and
electrons are in the following elements?
A) Ni B) Tc C) Ag D) Pb
What is a COMPOUND?
• A compound is a combination of
two or more different elements that
are combined chemically
– Most everyday substances are
compounds
– Approximately 10 million known
compounds
Add to Vocabulary Log!
Exit Ticket
1. What element has an atomic
number of 78? Write the
element name and symbol.
2. How many protons, neutrons,
and electrons does boron
have?