Slide 1 : Ch. 6: The Periodic Table 6.1 Organizing the Elements Mendeleev, Periodic Law, metals, nonmetals, metalloids
6.2 Classifying the Elements squares in the periodic table, periods and groups (p. 118), electron configurations, transition elements
6.3 Periodic Trends atomic size, ions, ionization energy, ionic size, electronegativityThe properties of the elements exhibit trends and these trends can be predicted with the help of the periodic table. They can also be explained and understood by analyzing the electron configurations of the elements. This is because, elements tend to gain or lose valence electrons to achieve the stable octet formation. (http://perfectprintables.myfuntips.com/documents/printableperiodictable.html)
How did chemists begin to organize the known elements? : How did chemists begin to organize the known elements? Chemists used the properties of elements to sort them into groups
Chlorine, bromine, and iodine have very similar chemical properties. (Dobereiner, 1829) 6.1
Vocabulary : Vocabulary In your notebook, define or know the characteristics of the following:
Group or family; period
Metals, nonmetals, metalloids
Alkali metals, alkaline earth metals, halogens
Noble gases, representative elements, transition metals, inner transition metals
Atomic radius, cation, anion, ionization energy, electronegativity
Mendeleev’s Periodic Table : Mendeleev’s Periodic Table In the 1800’s there were several different systems proposed, Mendeleev is given credit for an organized table
Mendeleev arranged the elements in his periodic table in order of increasing atomic mass.
The periodic table can be used to predict the properties of undiscovered elements. 6.1
An Early Version of Mendeleev’s Periodic Table : An Early Version of Mendeleev’s Periodic Table 6.1
The Periodic Law : The Periodic Law How is the modern periodic table organized?
In the modern periodic table, elements are arranged in order of increasing atomic number. (problems with Medeleev’s method) 6.1
The Periodic Law : The Periodic Law The periodic law: When elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties.
The properties of the elements within a period change as you move across a period from left to right.
The pattern of properties within a period repeats as you move from one period to the next. 6.1
Metals, Nonmetals, and Metalloids : Metals, Nonmetals, and Metalloids Metals, Metalloids, and Nonmetals in the Periodic Table 6.1
Metals, Nonmetals, and Metalloids : Metals, Nonmetals, and Metalloids 6.1 Metals are good conductors of heat and electric current.
80% of elements are metals.
Metals have a high luster, are ductile, and are malleable.
Metals, Nonmetals, and Metalloids : Metals, Nonmetals, and Metalloids 6.1 Nonmetals
In general, nonmetals are poor conductors of heat and electric current.
Most nonmetals are gases at room temperature.
A few nonmetals are solids, such as sulfur and phosphorus.
One nonmetal, bromine, is a dark-red liquid.
Metals, Nonmetals, and Metalloids : Metals, Nonmetals, and Metalloids 6.1 Metalloids
A metalloid generally has properties that are similar to those of metals and nonmetals.
The behavior of a metalloid can be controlled by changing conditions.
Metals, Nonmetals, and Metalloids : Metals, Nonmetals, and Metalloids Uses of Iron, Copper, and Aluminum 6.1
Metals, Nonmetals, and Metalloids : Metals, Nonmetals, and Metalloids If a small amount of boron is mixed with silicon, the mixture is a good conductor of electric current. Silicon can be cut into wafers, and used to make computer chips. 6.1
Squares in the Periodic Table : Squares in the Periodic Table The periodic table displays the symbols and names of the elements, along with information about the structure of their atoms. 6.2
Squares in the Periodic Table : Squares in the Periodic Table The background colors in the squares are used to distinguish groups of elements.
The Group 1A elements are called alkali metals.
The Group 2A elements are called alkaline earth metals.
The nonmetals of Group 7A are called halogens. 6.2
Slide 16 : 6.2
Electron Configurations in Groups : Electron Configurations in Groups Electron Configurations in Groups
How can elements be classified based on their electron configurations?
Elements can be sorted into noble gases, representative elements, transition metals, or inner transition metals based on their electron configurations. 6.2
Electron Configurations in Groups : Electron Configurations in Groups The Noble Gases
The noble gases are the elements in Group 8A of the periodic table. The electron configurations for the first four noble gases in Group 8A are listed below. 6.2
Electron Configurations in Groups : Electron Configurations in Groups The Representative Elements
Elements in groups 1A through 7A are often referred to as representative elements because they display a wide range of physical and chemical properties.
The s and p sublevels of the highest occupied energy level are not filled.
The group number equals the number of electrons in the highest occupied energy level. 6.2
Electron Configurations in Groups : Electron Configurations in Groups In atoms of the Group 1A elements below, there is only one electron in the highest occupied energy level.
In atoms of the Group 4A elements below, there are four electrons in the highest occupied energy level. 6.2
Representative Elements : Representative Elements 6.2
Representative Elements : Representative Elements 6.2
Transition Elements : Transition Elements Transition Elements
There are two types of transition elements—transition metals and inner transition metals. They are classified based on their electron configurations.
In atoms of a transition metal, the highest occupied s sublevel and a nearby d sublevel contain electrons.
In atoms of an inner transition metal, the highest occupied s sublevel and a nearby f sublevel generally contain electrons. 6.2
Transition Elements : Transition Elements Blocks of Elements 6.2
Periodic Trends : Periodic Trends Sodium chloride (table salt) produced the geometric pattern in the photograph. Such a pattern can be used to calculate the position of nuclei in a solid. You will learn how properties such as atomic size are related to the location of elements in the periodic table. 6.3
Trends in Atomic Size : Trends in Atomic Size What are the trends among the elements for atomic size?
The atomic radius is one half of the distance between the nuclei of two atoms of the same element when the atoms are joined.
In general, atomic size increases from top to bottom within a group and decreases from left to right across a period. 6.3
Trends in Atomic Size : Trends in Atomic Size 6.3
Trends in Atomic Size : Trends in Atomic Size 6.3
Ions : Ions Positive and negative ions form when electrons are transferred between atoms. 6.3
Ions : Ions 6.3 Some compounds are composed of particles called ions.
An ion is an atom or group of atoms that has a positive or negative charge.
A cation is an ion with a positive charge.
An anion is an ion with a negative charge.
Trends in Ionization Energy : Trends in Ionization Energy Trends in Ionization Energy
What are the trends among the elements for first ionization energy, ionic size, and electronegativity?
The energy required to remove an electron from an atom is called ionization energy.
The energy required to remove the first electron from an atom is called the first ionization energy.
The energy required to remove an electron from an ion with a 1+ charge is called the second ionization energy. 6.3
Trends in Ionization Energy : Trends in Ionization Energy Group and Periodic Trends in Ionization Energy
First ionization energy tends to decrease from top to bottom within a group and increase from left to right across a period. 6.3
Trends in Ionization Energy : Trends in Ionization Energy 6.3
Trends in Ionization Energy : Trends in Ionization Energy 6.3
Trends in Ionic Size : Trends in Ionic Size Trends in Ionic Size
During reactions between metals and nonmetals, metal atoms tend to lose electrons, and nonmetal atoms tend to gain electrons. The transfer has a predictable effect on the size of the ions that form.
Cations are always smaller than the atoms from which they form. Anions are always larger than the atoms from which they form. 6.3
Trends in Ionic Size : Trends in Ionic Size Relative Sizes of Some Atoms and Ions 6.3
Trends in Ionic Size : Trends in Ionic Size Trends in Ionic Size 6.3 Size generally increases
Trends in Electronegativity : Trends in Electronegativity Trends in Electronegativity
Electronegativity is the ability of an atom of an element to attract electrons when the atom is in a compound.
In general, electronegativity values decrease from top to bottom within a group. For representative elements, the values tend to increase from left to right across a period. 6.3
Trends in Electronegativity : Trends in Electronegativity 6.3
Summary of Trends : Summary of Trends What is the underlying cause of periodic trends?
The trends that exist among these properties can be explained by variations in atomic structure. 6.3 In your notebook, you should have a periodic table with all of the trends described: atomic size, ions, ionization energy, ionic size, eletronegativity