periodic trends

honors chem unit 3

the more charges there are, the _____ the attractive or repulsive force is

stronger

the closer together the particles are, the _____ the attractive or repulsive force is

stronger

the number of energy levels in an atom depends on what ___ it is in

row

the number of valence electrons depend on what ____ it is in

column

atomic radius

the distance from the nucleus to the outmost energy level

as you go down a column, atomic radius ___

increases

as you go across a row on the periodic table, atomic radius ___

decreases

cation

positive ion

cations are smaller than neutral atoms. why?

they lost an energy level

anion

negative ion

anions are larger than neutral atoms. why?

they have stronger electron-electron repulsion

largest common ions

I-, Br-

smallest common ions

Li+, Be+2, Na+, Mg+2

ionization energy

the energy needed to remove an electron from an atom

why is energy required to remove an electron from an atom?

to break the attraction between electrons and the nucleus

higher ionization energy means

that an electron in the atom is harder to remove

lower ionization energy means

that an electron in the atom is easy to remove

as you go down a column on the periodic table, ionization energy ________

decreases

as you go across a row on the periodic table, ionization energy ________

increases

electronegativity

attraction for electrons in a bond

why is it impossible to measure electronegativity for most of the noble gases?

they don't form bonds

more electronegative means that the atom

really wants electrons

less electronegative means

the atom doesn't want electrons

as you go down a column on the periodic table, electronegativity ________

decreases

as you go across a row on the periodic table, electronegativity __________

increases

very reactive element

if it reacts with many different types of elements, reacts relatively quickly, and releases lots of energy during the reaction

less reactive element

if it reacts with few different types of elements, reacts relatively slowly, and releases little energy during the reaction

the lower the element's ____, the greater its reactivity

ionization energy

why bigger atoms have lower ionization energy and high reactivity

The bigger an atom is, the farther its valence electrons are from the positively charged nucleus, so the weaker the force of attraction is between its valence electrons and the nucleus, so the easier it is to remove an electron from the atom. Therefore, the bigger a metal atom is, the lower its ionization energy is, and the higher its reactivity is.

for the metals, reactivity ____ as you go down a column of the periodic table

increases

why does reactivity increase as you go down a column of the periodic table?

More EL → Larger atoms → Lower IE

for the metals, reactivity ____ as you move to the right across a row of the periodic table

decreases

why does reactivity decreases as you move to the right across a row on the periodic table?

More protons → Smaller atoms → Higher IE

the greater the element's ____, the greater its reactivity

electronegativity

why is the bigger a nonmetal atom is, the lower its electronegativity is, and the lower its reactivity is

the bigger an atom is, the farther its valence electrons are from the positively charged nucleus, so the weaker the force of attraction is between its valence electrons and the nucleus, so the weaker the atom pulls on an attracts other electrons

for the nonmetals, reactivity ____ as you go down a column of the periodic table

decreases

why does nonmetal's reactivity decrease as you go down a column in the periodic table?

More EL → Larger atoms → Lower EN

for the nonmetals, reactivity ______ as you move to the right across a row of the periodic table

increases

why does reactivity increase as you move across a row of the periodic table?

More protons → Smaller atoms → Higher EN

which element is more reactive, sodium or potassium?

potassium; Potassium atoms are larger than sodium atoms because potassium has more energy levels. Therefore, potassium has a lower ionization energy, so it is easy for the atoms to lose electrons (which is how metals react).

Which element is more reactive, potassium or calcium?

potassium; Potassium atoms are larger than calcium atoms because potassium has more fewer protons, which results in a weaker force of attraction on the electron cloud. Therefore, potassium has a lower ionization energy, so it is easy for the atoms to lose electrons (which is how metals react).

Which element is more reactive, nitrogen or oxygen?

oxygen; Oxygen atoms are smaller than nitrogen atoms, because oxygen has more protons, which pull in the electron cloud closer to the nucleus. Therefore, oxygen has a stronger attraction for electrons (electronegativity) which means it is easier for the atoms to gain electrons (which is how nonmetals react).

Which element is more reactive, chlorine or iodine?

chlorine; Chlorine atoms are smaller than iodine atoms, because chlorine has fewer energy levels. Therefore, chlorine has a stronger attraction for electrons (electronegativity) which means it is easier for the atoms to gain electrons (which is how nonmetals react).

which of the following atoms is the largest?

platinum

what is bigger an O2- ion or an F- ion?

an O2- ion is bigger

A Ca2+ ion is _____ than a K+ ion because it has ________.

smaller, more electron-proton attraction

Calcium atoms ____________.

form cations by losing 2 electrons

A sodium ion (Na+1) has ___ energy levels and ___ valence electrons

2, 8

Sulfur has a ______ ionization energy than selenium does, because ______.

higher, its valence electrons are closer in toward the nucleus

The smaller an atom is, the ____ its ionization energy is and the ______its electronegativity is.

greater, higher

The electronegativity of an atom is most directly related to its

distance between the nucleus and its valence electrons

An atom of sodium will most likely lose ___ electrons to become a charge of ___ .

1, +1

An atom of nitrogen will most likely gain ___ electrons to become a charge of ___ .

3, -3