Chap 4

1
Chap 4

• Elements
• Atoms
• Ions

2
Essential Questions

• 1. What are atoms are there variations among
  atoms?
• 2. How do we write formulas?
• 3. What kind of information can we get from the
  Periodic Table?

3
What is some general informationconcerning
elements and nature

• gt 110 elements
• 89 occur in nature
• 9 elements make up most of earths crust
• oxygen most abundant in/on earth

4
What are the name and symbol of the first 36
elements on the Periodic Table

• Look them up and memorize them.
• Not number, not in order, just name and symbol

5
What are the components of Daltons Atomic Theory

• Elements made up of atoms
• Atoms of an element are identical
• Atoms of an element are diff than those of any
  other element
• Atoms combine in definite ratio to make cmpd
• Atoms indivisible and indestructible

6
What use could be made from this model

• Helps explain Law of Definite Composition(Proporti
  on)
• It can be used to predict how elements would
  combine

7
What are the fundamental parts of an atom

• Protons p
• neutrons no
• electrons e-

8
What is the history of the development of the
model of an atom

• Thomson 1890s discovered e-
• Kelvinplum pudding model 1910
• Rutherford discovered nucleus and formed the
  nuclear atom theory
• Chadwick 1932 discovered neutron

9
What is an isotope

• Atoms w/ same number of protons and a different
  number of neutrons
• (same atomic number different mass number)
• (same Z different A)

10
What is used to describe isotopes
11
How can you determine the number of p, no , and
e- in an isotope

• p Z
• no A-Z
• e- Z

12
Who first arranged elements in a table

• Mendeleev

13
What information concerning the make-up of an
atom can be found on the PT

• p
• no
• e-

14
What are the horizontal and vertical groupings
called on the PT

• Horiz Rows, periods
• Vert Columns, groups, families

15
What are the names of the important groups on the
PT

• Group I Alkali
• Group II Alkaline Earth
• Group VII Halogens
• Group VIII Noble Gases

16
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17
What are the major areas on the PT

• 
  metalloids?
• Innertransition(Rare Earth) metals?

18
What are the properties of metals

• Luster
• Good conductor of heat and electricity
• Maleable
• Ductile
• High m.p and b.p.

19
What are the properties of nonmetals

• Dull
• insulator
• brittle
• low m.p. and b.p.

20
What are the 7 diatomic molecules

• Br,I,N,Cl,H,O,F
• Brinkle-hof
• Br2 I2 N2 Cl2 H2 O2F2

21
What is an allotrope

• Different forms of the same element

22
Give an Example

• Carbon exists as diamond and graphite. It also
  exists as buckminsterfullerene

23
How does an atom and ion differ

• An ion is an atom that has either gained or lost
  and electron.
• (an atom that has acquired a charge by gaining or
  losing electrons)
• PROTON NUMBER DOESNOT CHANGE !

24
What is an anion

• A negative ion
• An atom that has gained electrons.
• The number of electrons is greater than the
  number of protons.
• O-2 p 8 e- 10

25
What is a cation

• A positive ion
• An atom that has lost electrons.
• The number of protons is greater than the number
  of electrons
• Ca2 p 20 e- 18

26
Describe the ion of Zn that has a 2 charge

• p 30
• no 35
• e- 28

27
Describe the ion of O that has a -2 charge

• p 8
• no 8
• e- 10

28
Det the number of protons, neutrons, and
electrons in

• 15 p
• 16 no
• 18 e-
• 56p
• 84 no
• 54 e-