BJU Physical Science (6th ed.) - Chapter 4
How many periods are on the periodic table?
7
family
A column of elements in the periodic table having similar valence electron arrangement, resulting in similar chemical properties; also know as a GROUP.
Electronegativity
A measure of an element's ability to attract and hold electrons when bonded to other atoms
Electronegativity
A measure of the ability of an atom in a chemical compound to attract electrons
Subscript
A number written slightly below and to the right of a chemical symbol that shows how many atoms of an element are in a compound.
period
A row in the periodic table of the elements; also called a SERIES
Group 1
Alkali metals +1
Group 2
Alkaline Earth Metals (+2)
Inner tansition metals
An element from either of two rows usually placed below the periodic table; a member of either the lanthanide or actinide series.
alkali meatals
An element in Group 1 of the periodic table, having one valence electron that it can easily lose to form a 1+ cation, making it extremely reactive
Nobel Gases
An element in Group 18 the periodic table having eight valence electrons that fill the outer energy level. (helium is and exception with only two.) With a full outer energy level, it is inert (i.e. nonreactive).
alkaline earth metal
An element in Group 2 of the periodic table, having two valence electrons that it tends to lose easily to become a 2+ cation, making it very reactive
metal
An element that is typically dense, solid, ductile, malleable, highly conductive, and chemically reactive, especially in the presence of nonmetal elements.
Nonmetal
An element that typically has four or more valence electrons and that does not exhibit the general properties of metals
Metaloids
An element with characteristics between those of metals and nonmetals; also called SEMICONDUCTORS
Tansition Metals
Any elements in Groups 3-12 of the periodic table typically having 1 or 2 valence electrons which it easily loses resulting in cations with charges of 1+ or 2+
mixed groups
Any of Groups 13-16 in the periodic table; so named because they contain metals, nonmetals, and metalloids. These groups are often named for the first element in the family
Explain why electronegativity changes as it does across a period.
As we move to the right across a period, the atomic radii decrease. This means that the valence electrons are closer to the nucleus, and so there is a greater attraction on the valence electrons. The nucleus pulls more strongly on bonded electrons in this smaller atom.
Explain why atomic radius changes as we move to the right across a period.
As we move to the right across a period, we add a proton and an electron to each additional element. This increases the attractive force on the electrons, pulling them closer to the nucleus. This makes the radius smaller.
Place in chronological order the following people who contributed to the development of the periodic table: Berzelius, Döbereiner, Mendeleev, Moseley, Newlands.
Berzelius, Döbereiner, Newlands, Mendeleev, Mosley
Does CN represent the element copernicium (112) or a compound of carbon and nitrogen? Explain.
CN must represent a carbon-nitrogen compound. If this symbol was representing copernicium, then the second letter (n) would be lowercase.
Noble gases
Chemically inert
Halogens
Contains nonmetals, 7 valence electrons in it's outermost energy level. Very reactive
Mendeleev
Created the first periodic table. Arranged elements by increasing atomic mass, left blank spaces for undiscovered elements, used rows and columns
Berzelius
Developed the modern symbols for the elements, Xx or X
Atomic radius
Distance from the center of the nuclei to the outer most energy level
valence electrons
Electrons on the outermost energy level of an atom, they are available to bond, go with the numbers at the top of the periodic table
Lavoisier
Elements combined in reactions (oxygen to create fire, combustion)
Metals
Elements that are good conductors of electric current and heat.
Nonmetals
Elements that are poor conductors of heat and electric current
Metalloids
Elements that have properties of both metals and nonmetals.
Octaves/octetes
Every 8 elements repeated their trends when arranged by atomic mass
Newlands
Expanded triads to octets,
Boyle and Lavoisier
First real chemists
cesium (group #)
Group 1
alkali metals
Group 1, 1 electron in outer level, very reactive
List the group number for each element. a. cadmium (1 point)
Group 12
carbon (group #)
Group 14
Group 17
Halogen Family, 7 valence electrons, highly reactive
What was Berzelius's contribution to the study of elements?
He created a system of chemical symbols that were based on the name of the element and the number of atoms. This became the basis for our modern system.
2 changes made to Mendeleev's original periodic table to produce the one that we use today.
He originally put the elements in columns according to atomic mass. This resulted in elements with similar characteristics being in rows. Mendeleev changed his table to list the elements in rows according to their atomic masses. Later the table was ordered by atomic number instead of atomic mass.
Name a key contribution that Robert Boyle made to the study of Chemistry.
He rejected the Greek concept of matter being mixtures of the five classical elements. He instead promoted the concept of matter consisting of indivisible particles of specific elements. He also promoted scientific inquiry and experimentation.
Periods
Horizontal rows on the periodic table
Why is the oxygen group considered one of the mixed groups?
It has elements that are metals, nonmetals, and metalloids.
On the basis of its position on the periodic table alone, what do we know about sulfur?
It is a nonmetal in Period 3 and Group 16. It has six valence electrons, which are located in the third energy level. It is similar to oxygen, selenium, and other Group 16 elements.
Describe a nonmetal and list its properties.
It is an element located to the right of and not touching the heavy stairstep line on the periodic table. It can be a gas, liquid, or solid. As a solid, it tends to be dull and brittle. It is a poor conductor. It tends to have four or more valence electrons. Its reactivity varies.
Using the periodic table, would you expect copper or gallium to exhibit more metallic properties? Explain.
It is farther to the left so it should exhibit more metallic properties
What information about a neutral atom of silicon does the periodic table tell us?
It is the fourteenth element, so it has fourteen protons and fourteen electrons. The average atomic mass implies that silicon-28 is a common isotope with fourteen neutrons. Since silicon is in Period 3, it has three energy levels. It's also in Group 14, so it has four valence electrons.
How does the shape of the periodic table reflect the order that we see in atoms and in the universe?
It reflects our understanding of atomic structure. The rows represent energy levels in the atom. The groups represent similarities in properties caused by similar electron configurations. The order in the universe and in atomic structure clearly shows up in the organization of the periodic table.
Why is the periodic table shaped the way it is
It's separated by how many energy levels are in each. The groups are arranged by elements with similar electron arrangements
Why did Berzelius establish his system of chemical symbols?
Many chemists had created symbols to represent elements and compounds. Berzelius created his system of chemical symbols to standardize the symbols to make sharing information easier.
mixed groups
Metals, nonmetals, metalloids
Group 13-16
Mixed groups to find the number of valence electrons face elements take the group number and subtract 10
What told Mendeleev where he should leave spaces for missing numbers and traits on the periodic table
Periodic law
Original Periodic Law
Properties of elements are a periodic function of their atomic mass
alkaline earth metals
Slightly less reactive then alkali metals
atomic radius
The distance from the center of an atom's nucleus to its outermost energy level.
Which family's atoms generally have eight valence electrons? What property do these electrons produce?
The noble gases have eight valence electrons and therefore tend to be nonreactive.
Using the periodic table, list two pairs of elements that would have been out of order on Mendeleev's periodic table (according to atomic mass) compared with our current table. Assume that scientists knew about all elements up to and including lead.
The pairs cobalt and nickel, argon and potassium, and tellurium and iodine would all have been out of order. (Accept any of these pairs.)
Define periodicity.
The repeated pattern of properties exhibited by elements when put in order of atomic mass or atomic number.
Where do the names of elements come from?
Their Greek and Latin roots, Greek/Roman gods (Thorium), people (Einsteinium), and places (Californium)
Why are electrons paired in electron dot notation?
They are paired in the actual atom.
What trait of alkali metals results from the fact that they easily lose their one valence electron?
They are the most reactive metals.
Of what elements did the ancient Greeks believe all matter consisted?
They believed that all matter formed from variable mixtures of earth, water, fire, air (or wind), and aether.
What type of ion do the alkali metals form and why?
They form a 1+ cation (positive ion) because they have one valence electron that they can easily lose.
All of the transition metals have at least how many energy levels? Explain.
They have at least four energy levels. The transition metals are all in rows 4-7, and rows represent energy levels.
What is similar about elements in a particular family?
They have similar atomic structure, especially their arrangement of electrons. They also all have the same number of valence electrons. The similarities in atomic structure result in the elements having similar chemical and physical properties.
Why do we need a periodic table?
While the specific form of a table may not be required, scientists recognized the need for a system to organize the information about chemical elements. Without some form of organization, the volume of information would be overwhelming.
electron-dot notation
a representation of an element's ability to attract and hold electrons when bonded to other atoms
periodic table
a table of the elements used to display there properties
Family/Group
a vertical column of elements in the periodic table
The family for calcium
alkaline-earth metals
valence electrons
an electron in the outermost energy level of a neutral atom
valence electron
an electron in the outermost energy level of an atom.
electron-dot notation
an electron-configuration notation in which only the valence electrons of an atom of a particular element are shown, indicated by dots placed around the element's symbol
Halogen
an element in Group 17 of the periodic table having seven valence electrons. It easily gains an electron, forming a 1- anion, which causes it to be highly reactive.
inner transition metals
elements that appear below the main body of the periodic table
transition metals
elements that form a bridge between elements on the left and right sides of the periodic table
The family for promethium
inner transition metals
Using the periodic table, classify strontium as either metal, nonmetal or metalloid.
metal
Using the periodic table, classify the following element as metal, nonmetal, or metalloid: antimony
metalloid
The family for lead
mixed group (or carbon family)
Group 18
noble gases
Using the periodic table, classify bromine as either metal, nonmetal or metalloid
nonmetal
How many valence electrons do the transition metals typically have?
one or two
Alchemist
one who practices medieval chemistry or tries to change metals into gold, wack
Arrange the following elements in order of increasing radius: oxygen, polonium, selenium, sulfur.
oxygen, sulfur, selenium, polonium
periodic law
the law that states the properties of the elements vary with their atomic numbers in a regular, repeated pattern.
Modern Periodic Law
the properties of the elements are periodic functions of their atomic numbers
State the periodic law.
the properties of the elements change in a repeating way with their atomic numbers.
Group 3-12
transition metals, 1 or 2 valence electrons
Döbereiner
triads based on similar chemical properties, atomic mass, & density, he used atomic mass, so his science was faulty since they didn't know about isotopes
the electron dot notation for the following element: magnesium
• •
The electron dot formation for indium
• • •
The electron dot notation for Fluorine
• • • • • • •
