Periodic Table Bases
What does the atomic number of an element represent?
The number of protons in the nucleus
what subatomic particle has a positive charge ?
proton
what happens to atomic radius as you move left to right across a period?
it decreases
What type of bond forms when electrons are transferred?
Ionic bond.
What is a compound?
A substance made of two or more different elements chemically bonded.
What information does the periodic table give about an element’s atomic mass?
the average mass of the element’s isotopes
which subatomic particle has no charge?
neutron
what happens to electronegativity as you move up a group?
it increases
What type of bond forms when electrons are shared?
covalent bond
What is a molecule?
Two or more atoms covalently bonded together.
What group are the alkali metals found in?
Group 1
where are electrons located in an atom?
in the electron cloud surrounding the nucleus
which element has a larger atomic radius: sodium or chlorine ?
What bond forms between a metal and a nonmetal?
ionic bond
What property measures how easily an atom loses an electron?
Ionization energy.
What block of the periodic table contains transition metals ?
The D-block
how do you calculate the number of neutrons in an atom?
atomic mass minus atomic number
what trend explains an atoms ability to attract electrons?
electronegativity
What is a valence electron?
An electron in the outermost energy level.
What is the octet rule?
Atoms tend to gain, lose, or share electrons to have 8 valence electrons.
Why are elements in the same group chemically similar?
they have the same number of valence electrons
what’s an isotope?
atoms of the same element with different numbers of neutrons.
Why do elements on the left side of the table lose electrons easily?
They have fewer valence electrons and lower ionization energy.
Why are noble gases usually unreactive?
They have full valence shells.
Why do ionic compounds conduct electricity when dissolved in water?
They dissociate into charged ions that can move freely.