CHAPTER 10
ATOMIC STRUCTURE &
THE PERIODIC TABLE
COMPOSITION OF MATTER
ElementsexamplesCompoundsexamplesPure substancesexamples-
STRUCTURE OF THE ATOM
Chemical symbol
Atom diagram (draw and label)
The __________ and the ____________ contribute to the mass of the
atom. The ____________ does not contribute to the mass because
___________________________________.
Atomic Number-
The atomic number ( can / cannot ) be changed for one specific
element.
Electron Cloud Model of the Atom:
Electron Orbital Model
1.
2.
Review
1. Write the chemical symbols for the elements:
Carbon:
Aluminum:
Hydrogen:
Oxygen:
Sodium:
2. List the names, charges, and locations of the three kinds of
particles that make up the atom.
3. What does an electron cloud represent?
HOMEWORK
1. An abbreviated way to write an element's name is to use a
______________________.
2. An atom's nucleus contains ________________________.
3. An atom's atomic number is the number of __________________ in
the nucleus.
Masses of Atoms
Mass Number-
How can you find the number of protons?
Average atomic mass-
Are there any elements that exist that actually have the average
atomic mass? _______________.
Isotopes-
ex.
Radioactive isotopesReview
1. A chlorine atom has 17 protons and 18 neutrons. What is its mass
number?
What is its atomic number?
2. How are the isotopes of an element alike?
How are they different?
3. Chlorine is used to treat most cidy water systems. The atomic
number of chlorine is 17. The two naturally occurring isotopes of
chlorine are chlorine 35 and chlorine 37. The average atomic mass
of chlorine is 35.45 u. Why does this indicate that most chlorine
atoms contain 18 neutrons?
4. All isotopes of an element have __________________
(similar/different) properties
HOMEWORK
1. What is an isotope?
2. From the mass number, how can you determine the number of
protons and neutrons?
3. How is the average atomic mass determined?
The Periodic Table
Elements on the periodic table are arranged in order of increasing
_______________________.
Vertical columns on the periodic table are called
_________________________.
As you move from element to element within a group, the elements
share ______________________ because ________________________.
The horizontal rows are called ___________________.
Stair step line indicates cut off between _____________ and
________________.
Elements on the boarder are called __________________ they are
characterized by _______________________.
ex.
Review
1. Use the periodic table to find the name, atomic number, and
average atomic mass of the following elements.
N
Ca
Kr
2. Give the period and group in which each of these elements is
found.
Period
Group
Nitrogen
Sodium
Iodine
Mercury
HOMEWORK
1. ____________ is a shorthand way of writing the name of an
element.
2. Draw a diagram of an atom and label the 3 parts
3. How are the electrons arrange in an atom?
4. How can you determine the number of neutrons in an atom?
5. The isotopes of an element are atoms of that same element that
have different numbers of ________________.
6. Elements in a group have the same number of _______________
and therefore, similar ____________________.
7. Indicate where metals, nonmetals, and metalloids are found on
the periodic table.
8. Which of the following would have similar properties to those of
Neon?
a. Aluminum
b. Argon
c. Arsenic
d. Silver
9. Boron is a ____________________
10. If the atomic number of Re is 75. The atomic mass of one of its
isotopes is 186. How many neutrons are in an atom of this isotope?
11. What holds the electrons in the atom?
BONDING
Chemical Compoud-
What does it mean?
Chemical bond 2 typesTypes of Chemical Bonds
Ionsex.
CationAnionIonic bond ex.
Covalent bondex.
Molecule-
Review
1. Compare and contrast ionic and covalent bonds.
2. What type of particle is formed by each of the following bonds?
IonicCovalent3. From the following list of symbols choose two elements that are
likely to form an ionic bond. Select two elements that would likely
form a covalent bond. Explain your choices.
Review
Write a formula for a compound with one calcium atom and two
fluorine atoms:
Write a formula for a compound with two aluminum atoms and
three sulfur atoms:
Why do elements form compounds?
FORCES
Van der Waaals Forces- Read p. 38 in text (end of 2.1)
2.2 COMPOSITION OF WATER
Why do you think water is important?
WATER MOLECULE
WHAT MAKES IT UNIQUE:
Physical properties-
Chemical Properties of Water
Polarity-
Hydrogen bonding-
CohesionDRAW EXAMPLE
Adhesion-
DRAW EXAMPLE
Heat capacity-
SOLUTIONS AND SUSPENSIONS
What is a solution?
Examples
ACIDS, BASES, AND pH
Water sometimes does what? How often?
WRITE THE EQUATION:
pH Scale:
What is it?
What does it indicate?
DRAW A SAMPLE SCALE
Acids-
Examples
Bases-
Examples
BuffersExamples-
HOMEWORK
1. What does it mean when a molecule is said to be “polar”?
2. Explain how hydrogen bonds between water molecules
occur
3. Draw a sample water molecule, and place the partial charges
in correct place
4. Why is water such a good solvent?
5. What is an acid? What is a base?
6. The acid HF, or hydrogen fluoride, can be dissolved in pure
water. Will the pH of the solution be greater or less than 7?
EXPERIMENT TIME!!