Question | Answer |
actinide | one of the 14 elements with atomic numbers from 90 (thorium, Th)
through 103 (lawrencium, Lr) |
alkali metal | one of the elements of Group 1 of the periodic table (lithium,
sodium, potassium, rubidium, cesium, and francium) |
alkaline-earth metal | one of the elements of Group 2 of the periodic table
(beryllium, magnesium, calcium, strontium, barium, and radium) |
anion | a negative ion |
atomic radius | one-half the distance between the nuclei of identical atoms that
are bonded together |
cation | a positive ion |
electron affinity | the energy change that occurs when an electron is acquired by
a neutral atom |
electronegativity | a measure of the ability of an atom in a chemical compound to attract electrons OR a measure of pull between to atoms for electrons |
halogen | one of the elements of Group 17 (fluorine, chlorine, bromine, iodine,
and astatine) |
ion | an atom or group of bonded atoms that has a positive or negative
charge |
ionization | any process that results in the formation of an ion |
ionization energy | the energy required to remove one electron from a neutral
atom of an element |
lanthanide | one of the 14 elements with atomic numbers from 58 (cerium, Ce)
to 71 (lutetium, Lu) |
main-group element | an element in the s-block or p-block |
periodic law | the physical and chemical properties of the elements are periodic
functions of their atomic numbers |
periodic table | an arrangement of the elements in order of their atomic numbers
so that elements with similar properties fall in the same column, or group |
transition element | one of the d-block elements that is a metal, with typical metallic properties |
valence electron | an electron that is available to be lost, gained, or shared in the
formation of chemical compounds |
What is the most reactive nonmetal? | Fluorine, F |
What is the most reactive metal? | Fracium, Fm |
The most nonreactive group of elements are the __________. | Noble Gases |
Periods run | horizontally |
Groups run | vertically |
In the modern periodic table, elements are ordered according to | increasing atomic number |
Who created the first periodic table? | Medeleev |
The first periodic table was ordered according to | increasing atomic mass |
What is atomic mass? | the weighted average of natural occurring isotopes |
Who discovered atomic number? | Henry Mosely |
Group and Period Trends: Atomic radii within a family | increases (number of electrons increases) |
Group and Period Trends: Atomic radii within a period | decreases (Protons are added; stronger pull toward nucleus) |
Group and Period Trends: Ionization energy within a family becomes | smaller (easier to take electron from bigger atoms because there are more shells) |
Group and Period Trends: Ionization energy within a period becomes | harder (more difficult from non-metals and going to noble gases which are "perfect") |
Do metals or nonmetals have a greater affinity for electrons? | nonmetals |
Do large atoms or small atoms have a greater electron affinity? | small atoms |
In chemistry, less energy means | greater stability |
High electron affinity means | low energy |
Group and Period Trends: Electronegativity within a group | decreases |
Group and Period Trends: Electronegativity within a period | increases (toward fluorine) |
Which element has the highest electronegativity? | fluorine |
Metals tend to form ______ ions, while nonmetals tend to form _______ ions. | positive; negative |
Cations tend to be _____ then it's neutral atom, while anions tend to be _______ then it's neutral atom. | smaller; bigger |
Types of bonds are determined by | electronegativity |