Periodic Table groups.notebook

Periodic Table groups.notebook
September 11, 2014
Sep 11­8:55 AM
Sep 11­8:55 AM
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Periodic Table groups.notebook
September 11, 2014
How is the Periodic Table Organized? • Elements are listed in order of atomic number (number of protons)
• Elements are grouped according to their electron configuration (ex: all elements in the first column end in s1
Horizontal rows – PERIODS (1­7)
Vertical columns – GROUPS/FAMILIES (1­18)
Metals: luster when clean
high electrical conductivity
ductile – can be drawn into wires
malleable – can be flattened into sheets
Non metals: nonlustrous
poor conductors of electricity
Semi­metals/metalloids:properties of both metals and nonmetals
Where are they located on the periodic table?
Draw a ‘staircase’ under boron. The elements on either side of this staircase (except aluminum) are semimetals; that is: B, Si, Ge, As, Sb, Te, Po, St. Excluding these elements, metals are located to the left of the staircase, and nonmetals are located to the right.
Sep 10­8:10 AM
Sep 10­8:17 AM
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Periodic Table groups.notebook
September 11, 2014
Chemical Families
Alkali metals (group 1)
• have one valence electron
• highly reactive (i.e. with water)
• react with halogens to produce salts in a 1:1 ratio (ex: NaCl)
• soft, shiny when cut, oxidize in air
• not found in nature in pure form Potassium in water video
Sep 10­8:20 AM
Alkaline earth metals (group 2)
• have two valence electrons
• quite reactive (i.e. with water)
• extracted from mineral ores (‘earths’)
• react with halogens to produce salts in a 1:2 ratio (ex: MgBr2)
• harder than group 1 metals
• not found in nature in pure form
Sep 10­8:22 AM
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Periodic Table groups.notebook
September 11, 2014
Transition Metals (groups 3­12)
• typical metals; vary greatly in reactivity
• most form brightly colored compounds
• form compounds with multiple elements
Sep 10­8:26 AM
Halogens (group 17)
• have seven valence electrons
• F and Cl: yellow/green gases
• Br: brown/red liquid
• I: purple solid
• most combine with elements from group 1 or 2 to form salts
Sep 10­8:29 AM
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Periodic Table groups.notebook
September 11, 2014
Noble gases (group 18)
• have eight valence electrons
• ‘inert’: least reactive of all elements
• all gases at room temp and pressure
Sep 10­8:31 AM
Periodic Table Video
Sep 10­8:33 AM
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Periodic Table groups.notebook
CHE 11
September 11, 2014
Periodic Table Practice
Part A: Multiple Choice: Write the answer in the blank provided.
___ 1. Elements that are found in group 2 are:
a) halogens
c) alkaline earth metals
b) transition metals
d) alkali metals
___ 2. Boron is a:
a) nonmetal
b) metal
c) metalloid
d) none of these
___ 3. Hydrogen is a:
a) nonmetal
b) metal
c) metalloid
d) none of these
___ 4. Tellurium (Te) has the electron configuration ending:
a) 5p4
b) 4p5
c) 4p4
d) 5d4
___ 5. An element that has an electron configuration ending that is an
exception to the trend is :
a) chlorine
b) hydrogen
c) silver d) silicon
___ 6.
a)
b)
c)
d)
The noble gases:
react violently with water
combine with group 1 elements to form salts
are the least reactive of all the elements
must be stored under oil
Sep 11­9:56 AM
___ 7. Group number seventeen elements are the
a) alkali metals
c) noble gases
b) transition metals
d) halogens
___ 8. Transition metals have electron configuration endings involving:
a) d orbitals c) p orbitals
b) f orbitals
d) s orbitals
___ 9. All alkaline earth metals have the electron configuration ending:
a) s1
c) s2
1
b) 1s
d) 1s2
___ 10. These elements are soft enough to be cut with a knife and must be
stored under oil.
a) transition metals
c) alkali metals
b) halogens
d) alkaline earth metals
___ 11. The symbol for the element that is found in period 3, group 2 is a) Ca
c) Be
b) Mg d) Al
___ 12. Chromium (Cr) has the electron configuration ending:
a) 4d4
b) 4d5
c) 3d4
d) 3d5
Sep 11­9:57 AM
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Periodic Table groups.notebook
September 11, 2014
13. An element is shiny and conducts heat and electricity very well. It must be:
a) a nonmetal
c) a halogen
b) a metal
d) a noble gas
14. Which of the following is NOT a property of the alkali metals?
a) soft
b) form salts with halogens in a 1:2 ratio
c) react with water to produce a base
d) not found in nature in their pure form
15. An atom has the electron configuration ending 5p6. What could this element NOT be?
a) Xe
b) I­
c) Ba2+ d) Sr2+
Part B: Short answer.
1. For each of the following, give the electron configuration, circle the orbitals containing the valence electrons, and draw the electron dot symbol.
a) C
b) Al
c) Cu
d) O ­2
Sep 11­9:57 AM
2. Explain, using what you know about valence electrons, why alkali metals tend to form a +1 charge and halogens tend to form a –1 charge. Include examples of electron configurations in your answer.
Sep 11­9:58 AM
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Attachments
Potassium in water video
Periodic Table Video