Periodic Table 1
The electrons involved in chemical reactions are these.
What are valence electrons?
The electrons in the outer energy level are called this.
What are valence electrons?
The atomic number tells you this.
What is the number of protons (and electrons) an atom of an element should have?
The reactivity of an element is dependent on this.
What is the ability of an atom to either completely fill or empty its outer most energy level?
The periodic or repeating pattern of elemental properties observed by Mendeleev in his table permitted this
What is the prediction of unknown elements?
These are the properties of metals.
What are 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 this.
What is unreactive?
Metalloids are known to have this property which concerns the ability to conduct heat and electricity at certain temperatures.
What is semiconductivity?
The columns on a periodic table are called this.
What are groups?
These are the properties of metalloids.
What are many properties of both metals and nonmetals?
Elements in groups 3-12 have are less reactive with each proton added to the nucleus for this reason.
What is it is more difficult to achieve an empty valence energy level?
Mendeleev organized the elements of his periodic table according to this.
What is increasing atomic mass?
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.
What are halogens?
Elements in groups 13-16 contain one or more of these class of hybrid type elements.
What are metalloids?
Elements in the same group share this.
What are the same number of valence electrons
These are the properties of nonmetals.
What are brittleness, low boiling/melting points, dull, and are good insulators?
Group 18 elements are extremely nonreactive nonmetals known as this.
What are noble gases?
Extremely reactive elements in group 1 have only 1 valence electron and are known as this.
What are alkali metals?
The rows on a periodic table are known as this.
What are periods?
The three classes of elements are these.
What are 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.
What is group 1 or alkali metals?
The modern periodic table is organized according to this.
What are by increasing atomic number?
Increasing numbers of electrons are always added here on an atom.
What is at the lowest energy unoccupied energy level?
The Actinides and Lathanides are two subgroups of radioactive elements that belong to this class of elements.
What are metals?
Very reactive elements in group 2 have only 2 valence electrons and are known as this.
What are alkaline Earth metals?