#16: Elements and the Periodic Table
READING GUIDE
Atoms:
Compound:
A. Discovering Elements
a. Greek Philosophers thought….
b. That was not true, but chemists did start discovering…..
-----------------------------------------------------------------------------------------------------------STOPPING TO THINK 1
1. In what way were the ancient Greek philosophers right about elements?
2. In what ways were the ancient Greek philosophers wrong?
-----------------------------------------------------------------------------------------------------------B. Mendeleev and the Periodic Table of the Elements
a. Mendeleev published the first…..
b. He used data that other scientists had collected, and when he
arranged them according to their __________________________ and
__________________________________________ he noticed that there
was a pattern.
-----------------------------------------------------------------------------------------------------------STOPPING TO THINK 2
1. How did Mendeleev build on other scientists’ work?
2. How did other scientists build on Mendeleev’s work?
C. The Modern Periodic Table
a. Atomic Number:
b. An element’s location on the periodic table can help you predict its….
c. Metalloids are located _____________________________________ on
the periodic table, and their properties are…..
-----------------------------------------------------------------------------------------------------------STOPPING TO THINK 3
Use the Periodic Table of the Elements on the next page to decide whether each of the
following is a metal or a nonmetal:
Lithium (Li) Carbon (C) Sulfur (S) Calcium (Ca) Titanium (Ti) Bromine (Br) -----------------------------------------------------------------------------------------------------------d. Reactivity:
e. The least reactive elements on the periodic table are….
f. The most reactive metals are….
g. The most reactive nonmetals are …..
-----------------------------------------------------------------------------------------------------------STOPPING TO THINK 4
Find Magnesium on the periodic table.
 What is Magnesium’s chemical symbol? ______________________
 What family does Magnesium belong to?_______________________
 Is Magnesium a solid, a liquid, or a gas? __________________
 Based on it’s family, would you expect Magnesium to be very reactive,
somewhat reactive, or not reactive at all? _____________________________
-----------------------------------------------------------------------------------------------------------D. Forming Compounds
a. molecule:
b. Draw a water molecule:
c. Compounds have different properties than the elements that form them.
For example….
-----------------------------------------------------------------------------------------------------------STOPPING TO THINK 5
What are two ways that compounds are different from the elements that form them?
-----------------------------------------------------------------------------------------------------------E. Chemical Names and Formulas
a. chemical formula:
b. In the chemical formula H20, the “2” means….
-----------------------------------------------------------------------------------------------------------STOPPING TO THINK 6
The chemical formula for baking soda is NaHCO3. What elements are in baking soda?
How many of each kind of atom is represented by the formula for baking soda?
-----------------------------------------------------------------------------------------------------------F. Classifying Matter: Elements, Compounds, and Mixtures
a. Examples of elements are…..
b. Examples of compounds are….
c. Everything that isn’t a pure element or compound is a mixture, examples
of mixtures are….
ANALYSIS
1. Use the Periodic Table of the Elements to find out which atoms make up a molecule
for each of the substances listed.
4. Explain the relationship between an atom and a molecule. Draw labeled pictures as
part of your explanation! Give an example.