test 5 Flashcards
who mostly gets the credit for the development of the modern periodic table?
Dmitri Mendeleev
who arranged the elements by their atomic masses?
Dobereiner
Newlands
Mendeleev
who 1st arranged the elements in order of increasing atomic numbers?
Moseley
a vertical column of elements that usually have similar physical and chemical properties due to their similar electron configuration
group or family
horizontal rows of elements
period or series
appears at the top left of the cell
atomic number
appears above the symbol
name
1, 2, or 3 letters that is the most prominent item in the cell
symbol
weighted average that’s always given in four significant digits.
atomic mass
The number and location of electrons in each occupied energy level in the neutral atom are listed below the atomic mass
electron structure by energy level
the distance from the center of an atom’s nucleus to its outermost electron
atomic radius
atomic radius_ from left to right and _ from top to bottom
decrease, increase
positive ions that are _ than their parent atoms because they have fewer electrons
cations, smaller
what type of atoms form cations easiest
metals
for a single neutral atom in the gaseous state the minimum energy required to remove the first electron from its outermost shell to make it a cation
first ionization energy
the amount of energy required to add an electron to a neutral atom to form a negative ion, or anion
electron affinity
what are atoms that have lost or gained electrons?
ions
what is the measure of the attraction between the nucleus and valence electrons?
electronegativity
what is the lightest element and the most abundant in the entire universe?
hydrogen
what is the most abundant alkali metal?
sodium
the group 2 (2a) metals which contain 2 valence electrons
alkaline-earth metals
_compounds are the basis for life
carbon
describe oxygen
gas that form about 21% of the earth’s atmosphere. it is slightly soluble in water and is the most abundant element by mass in the earth’s crust
halogens form_ when combined with metals
salts
why are noble gases called noble gases?
they do not react with other elements except under unusual conditions of pressure and temperature
which elements conduct heat and electricity well and are usually malleable?
metals
which elements are usually gases or soft, crumbly solids
non metals
metals such as zinc, calcium, and iron combine with sulfur to form
sulfides
oxygen combines with other elements to form
oxides
where are alkali metals
group one
period 2 and down
(group one excluding hydrogen)
where are alkaline earth metals
all of group 2
where are transition metals
groups 3-12 excluding the last element in both group 11 and 12
where is the boron family
group 13 excluding the last element
where is the carbon family
group 14 excluding the last element
where is the nitrogen family
group 15 excluding the last element
where is the oxygen family
group 16 excluding the last element
where are the halogens
group 17 excluding the last element
where are the noble gases
group 18 excluding the last element
how many electrons are in helium’s outer shell
2
members of the halogens
fluorine chlorine bromine iodine astatine
members of the noble gases
helium neon argon krypton xenon radon
members of the alkali metals
lithium sodium potassium rubidium cesium francium
members of the alkaline earth metals
beryllium magnesium calcium strontium barium radium
define noble gases
Group 18 (8A) elements. They have full outer energy levels making them very stable and essentially inert.
