Periodic Table 1
The name of the electrons involved in chemical reactions.
Valence electrons
The electrons in the outer energy level are called this.
valence electrons
The atomic number tells you this.
the number of protons (and electrons) an atom of an element should have
The reactivity of an element is dependent on this.
the ability of an atom to either completely fill or empty its outer most energy level
An element is
A type of atom defined by the amount of protons in its nucleus.
These are the properties of metals.
conductivity, high melting points, most are solids at room temperature, shiny, ductile, and malleable
An atom with a completely full outer most (valence) energy level is
unreactive
Metalloids are known to have this property which concerns the ability to conduct heat and electricity at certain temperatures.
semiconductivity
The columns on a periodic table are called this.
groups
These are the properties of metalloids.
many properties of both metals and nonmetals
As proton numbers increase across a period, the electronegativity of elements......
Increases
the elements in the periodic table are arranged according to
increasing atomic number
Group 17 contains highly reactive nonmetals with seven valence electrons that tend to react violently with alkali metals and are more commonly known as this.
halogens
Elements in groups 13-16 contain one or more of these class of hybrid type elements.
metalloids
Elements in the same group share this.
same number of valence electrons
These are the properties of nonmetals.
brittleness, low boiling/melting points, dull, and are good insulators
Group 18 elements are extremely nonreactive nonmetals known as this.
noble gases
Extremely reactive elements in group 1 have only 1 valence electron and are known as this.
alkali metals
The rows on a periodic table are known as this.
periods
The three classes of elements are these.
metals, metalloids, and nonmetals
An unknown metal is extremely soft, silvery grey and very reactive when floated on water. It is likely that the unknown metal belongs to this group of elements.
group 1 or alkali metals
Element X has an atomic number of 51 and mass number of 103. Element Y has an atomic number of 52. The mass number of Element Y relative to Element X could be....
The same, higher or lower than the mass number of Element X depending on how many neutrons it has.
Increasing numbers of electrons are always added here on an atom.
lowest energy level that has space for more electrons.
The Actinides and Lathanides are two subgroups of radioactive elements that belong to this class of elements.
metals
Very reactive elements in group 2 have only 2 valence electrons and are known as this.
alkaline Earth metals