Bell Ringer
• Answer each question with True or False.
1) The “prediction” part of the scientific method can
be written as: if the hypothesis is true, then ___.
2) The scientific method ends with data analysis
3) If something moves, we can consider it to be alive.
4) Metabolism = energy
5) Homeostasis is another way of saying that living
things are organized in a way that makes sense.
The Chemistry of Life
First, Some Terms...
• Matter –
First, Some Terms...
• Matter – anything that occupies space and
has mass.
• Mass –
First, Some Terms...
• Matter – anything that occupies space and
has mass.
• Mass – the amount of matter an object has.
First, Some Terms...
• Matter – anything that occupies space and
has mass.
• Mass – the amount of matter an object has.
• Mass is NOT the same as weight.
First, Some Terms...
• Matter – anything that occupies space and
has mass.
• Mass – the amount of matter an object has.
• Mass is NOT the same as weight.
• Weight – the force produced by gravity
pulling down on mass.
So, where would your
weight be different?
The moon’s gravity is weaker than Earth’s, so you would weigh less.
Would your mass change on the moon?
The moon’s gravity is weaker than Earth’s, so you would weigh less.
Would your mass change on the moon? NO!
Some Chemistry...
• Element – a substance that
cannot be broken down into
simpler kinds of matter.
• All things on earth (living or
nonliving) are made up of
elements.
• Over 100 elements have
been discovered.
Some Chemistry...
• Element – a substance that
cannot be broken down into
simpler kinds of matter.
• All things on earth (living or
nonliving) are made up of
elements.
• Over 100 elements have
been discovered.
What elements do you know of?
Some Chemistry...
• Element – a substance that
cannot be broken down into
simpler kinds of matter.
• All things on earth (living or
nonliving) are made up of
elements.
• Over 100 elements have
been discovered.
Where can we find a list of all the elements?
Periodic Table
• The periodic table tells us a chemical’s:
– Atomic Number 
10
– Symbol

Ne
– Atomic Mass

20.18
Some Chemistry...
• Four elements are of utmost importance to
life on earth.
• They are found in over 90% of the mass of
all living things.
Some Chemistry...
• Four elements are of utmost importance to
life on earth.
• They are found in over 90% of the mass of
all living things.
Carbon
Oxygen
Hydrogen Nitrogen
The Atom
• The smallest particle of an element is an atom.
The Atom
• The smallest particle of an element is an atom.
• Atoms determine the structure and properties of
the matter they compose.
• Atoms are so small, they can not be directly
observed.
The Atom
• The middle of the atom is called the nucleus.
– It contains protons (+ charge)
– And neutrons (no charge)
The Atom
• The middle of the atom is called the nucleus.
– It contains protons (+ charge)
– And neutrons (no charge)
• An element’s atomic
number is the number
of protons it contains.
The Atom
• The middle of the atom is called the nucleus.
– It contains protons (+ charge)
– And neutrons (no charge)
• An element’s atomic
number is the number
of protons it contains.
What is this atom’s
atomic number?
The Atom
• The middle of the atom is called the nucleus.
– It contains protons (+ charge)
– And neutrons (no charge)
• An element’s atomic
number is the number
of protons it contains.
4
Be
9.01
The Atom
• The middle of the atom is called the nucleus.
– It contains protons (+ charge)
– And neutrons (no charge)
• An element’s mass
number is the number
of protons + neutrons.
The Atom
• The middle of the atom is called the nucleus.
– It contains protons (+ charge)
– And neutrons (no charge)
• An element’s mass
number is the number
of protons + neutrons.
What is this atom’s
mass number?
The Atom
• The middle of the atom is called the nucleus.
– It contains protons (+ charge)
– And neutrons (no charge)
• An element’s mass
number is the number
of protons + neutrons.
4
Be
9.01
The Atom
4
• So, what’s up with the decimal
in Beryllium’s mass number?
Be
9.01
The Atom
4
• So, what’s up with the decimal
in Beryllium’s mass number?
Be
9.01
• All atoms of the same element have the
same number of protons.
That’s what identifies it as that specific element!
The Atom
4
• So, what’s up with the decimal
in Beryllium’s mass number?
Be
9.01
• All atoms of the same element have the
same number of protons.
• Atoms of the same element, however, may
have a different number of neutrons.
• Atoms of the same element that have
different numbers of neutrons are called
isotopes.
The Atom
4
• So, what’s up with the decimal
in Beryllium’s mass number?
Be
9.01
• Beryllium’s mass number is an average of
the mass of its different isotopes.
The Atom
• Electrons, negatively charged particles, move
around the nucleus.
• Electrons have very little mass.
• Most important,
electrons are involved
in bonding.
Scroobius Pip vs. Dan Le Sac
“Development”
Discover
an
Element
Your job is to create a mini-poster about an element.
•
• The poster should include:
– The name of the element and its symbol.
– The atomic number and the atomic mass number.
– What phase is your element found in at room
temperature?
– Where is this element found in nature?
– How is your element used commercially (by humans)?
– What compounds is your element found within?
– Does your element have isotopes? What are they?
– At least one interesting fact about your element.
– At least two illustrations
• Use color, make it look nice!
Exit Slip
• Answer the following questions
based upon the atomic nucleus
pictured to the right.
1)What element is this?
a) Hydrogen
b) Lithium
c) Nitrogen
d) Oxygen
Exit Slip
• Answer the following questions
based upon the atomic nucleus
pictured to the right.
2) What is the atomic number of this element?
a) 7
b) 4
c) 3
d) 8
3) How can we tell that this atom may be an isotope?
a) there are more neutrons than protons
b) there are more protons than neutrons
c) there are enough neutrons to balance the
charge of the protons
d) this atom has an overall negative charge
Exit Slip
• Answer the following questions
based upon the atomic nucleus
pictured to the right.
4) If a proton was added to this atom, what
would happen?
a) it would become an isotope of the
original element
b) it would become a new element
c) there would be no change
d) it’s atomic mass would increase, but not
its atomic number