CHEMISTRY
CHAPTER 6 NOTES
MRS. SINGH
SXN 6.1 Development of the Modern Periodic Table
 In _______, the Russian chemist Dmitri Mendeleev noted that when
the known elements were placed in order of increasing atomic
_________, their properties repeated in a regular _____________, a
periodic pattern.
 Mendeleev made a table in which her arranged the _______________
in order of increasing atomic mass into ______________ with
_________________ properties.
 From this table, Mendeleev predicted the properties of three elements
that were undiscovered at the time. When these elements – scandium
(
), gallium (
) , and germanium (
) were soon
discovered and found to have most of the _______________
properties, Mendeleev’s periodic table was _________________ in
the scientific world.
 Besides the addition of newly discovered elements, the only
___________ change in the organization of the periodic table since
Mendeleev’s time is that the elements are now arranged in order of
atomic _______________ instead of atomic ___________.
The Modern Periodic Table
 The elements are arranged in the periodic table in order of
____________________ atomic number in horizontal rows called
_______________. Because the pattern of properties repeats in each
new row of elements, the elements in a column have ______________
properties and are called a ____________ or family of elements.
 The groups are designated with a ___________ and the letter ____ or
_____.
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 Groups 1A through 8A are called the main group or representative
__________.
 The Group B elements are called the ________________ elements.
 Elements are divided into three main classes - _____________,
metalloids, and ______________.
 Metals are generally __________ solids and are good
_______________ of heat and electrical ______________. Some
groups of elements have names. For examples, the first two groups of
metals are called the _____________ metals and the alkaline
___________ metals.
 Most of the elements to the right of the heavy stair-step line in the
periodic table are _________________, which are generally either
______ or brittle ____________ at room temperature.
 Group 7A elements are commonly called ______________, and group
8A elements are the ___________ gases. Many of the elements that
border the stair-step line are metalloids, which have some of the
characteristics of __________ metals and nonmetals.
Practice
Match each element in Column A with the best matching description from
Column B. Column A element may match more than one description from
Column B.
1.
2.
3.
4.
5.
6.
7.
Column A
strontium
chromium
iodine
nitrogen
argon
rubidium
silicon
Column B
a. halogen
b. noble gas
c. alkaline earth metal
d. metalloid
e. alkali metal
f. representative element
g. transition element
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HOW TO WRITE A FORMULA
1. Write down the chemical symbols for each atom or
element – the metal first then the nonmetal:
Ex. Aluminum oxide
Al
O
Calcium oxide
Ca O
2. Write the valence/charge above each symbol.
Al +3
O -2
Ca +2 O -2
3. Now criss-cross and reduce if possible
Al +3
Al2O3
O –2
Ca +2 O –2
Ca2O2 reduces to CaO
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