Chapter 6 Flashcards
99
Percent of atoms of the human body that come from 4 elements (C, H, N, and O).
macronutrients
Elements that are needed in large quantities by your body.
trace elements
elements that are needed in very small quantities to maintain optimum health.
ionic
A compound formed by the bonding of 1 metal & 1 non-metal as a result of 1 or more electrons being transferred from the metal to the non-metal.
molecular
A covalent compound formed by the bonding of 2 or more non-metals as a result of 1 or more electrons being shared (equally or unequally) between the atoms.
Mendeleev
The chemist that used density (a physical property) and increasing atomic mass to arrange all known elements into the first periodic table; also recognized many repeating patterns in the ratio of atoms in various compounds.
periodic
A term that describes any pattern that repeats at regular intervals.
atomic radius
one-half the distance between the nuclei of 2 identical atoms that are bonded together; decreases from left to right across a period and increases down a group or family.
electronegativity
The ability of an atom to attract another atom’s electrons when bound to that other atom; increases from left to right across a period and from bottom to the top of a group of elements.
ionization
The energy required to remove an electron from an atom; increases from left to right across a period and from the bottom to the top of a group of elements.
francium
The last naturally occurring element discovered in 1939; an atomic number of 87.
modern periodic table
Arranges elements in order of increasing atomic number and electron configurations.
S
Single, spherical orbital that can hold a maximum of 2 electrons.
P
Contains 3 dumbbell-shaped orbitals which can hold a maximum of 6 electrons.
D
Contains 5 clover-shaped orbitals which can hold a maximum of 10 electrons.
F
Contains 7 orbitals of various complex conical and planar nodes which can hold a maximum of 14 electrons.
alkali
Soft & extremely reactive Group 1 metals that have 1 electron in their outer energy level; silver, shiny, low density; tend to lose this one electron to become a +1 ion when reacting with a non-metal.
alkaline earth
Harder & less reactive Group 2 metallic elements that have 2 electrons in their outer energy level; tend to lose 2 electrons to other non-metals to have a charge of +2.
transition metals
The less reactive metals in Groups 3-12 that individually may have various numbers of electrons in the outer energy level and therefore complex bonding properties; most have unfilled d-orbitals.
Carbon
An element on the periodic table that is special because it can accept or donate electrons while forming chemical bonds.
nitrogen
An element on the periodic table that tends to gain 3 electrons giving it a -3 charge.
oxygen
An element on the periodic table that tends to gain 2 electrons giving it a -2charge.
halogens
The reactive non-metals in group 7a of the periodic table that contain 7/8 electrons in their outermost energy level; when forming ionic compounds they pull 1 electron away from various metals.
noble gases
Inert or unreactive gaseous elements of group 8 on the periodic table; have full outer energy levels preventing them from bonding with other elements.
valence
Electrons in the outermost energy level (highest unfilled) of an atom that are the only electrons involved in the formation of ionic or covalent chemical bonds.
rule of chemical bonding
Atoms either lose, gain or share valence electrons so that they obtain an electron configuration similar to that of a noble gas.
Lewis
A diagram showing one dot for each valence electron an atom has, these dots surround the element symbol of the atom.
Ionic Radius Trend
The more + an ion is, the smaller the ionic radius while the more - an ion is, the larger the ionic radius.
