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?
These are the properties of metals.
What are shiny, hard 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?
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?
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?
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?