1C: The Periodic Table Flashcards
Explain core charge, and its trend.
Measure of the attractive force felt by valance electrons in the outer shell towards the nucleus.
CONSTANT DOWN GROUP + INCREASES ACROSS PERIOD (->)
Explain atomic size, and its trend.
Overall distance from one side of an atom to the other.
DECREASES ACROSS PERIOD + INCREASES DOWN GROUP (./)
- decreases across period: more electrons + protons = more electrostatic pull
- down group: more shells added
Group the trends together
Constant across group, increases across period (->): Core charge
Increases down group, decreases across period (./): Atomic size/radius, metallic character, metal reactivity
Decreases down group, increases across period (/’): Electronegativity, non-metal reactivity, first ionization energy
Explain electronegativity and its trend.
The ability of an atom to attract electrons to itself.
DECREASES DOWN GROUP + INCREASES ACROSS PERIOD
- Atoms on right-side of table are close to filling valence shells (EN increases)
Explain first ionization energy, and its trend.
Energy required to remove the first valence electron.
INCREASES ACROSS PERIOD + DECREASES DOWN GROUP (./)
- the further away the electron is from the nucleus, the easier it is to pull away
- down group: electron increasingly distant (less energy)
- increases across period: more protons- electrons will be more tightly held
Explain metallic character, and its trend.
Tendency of atom to lose electron instead of gaining an electron to fill its valence shell.
INCREASES DOWN GROUP + DECREASES ACROSS PERIOD
- non-metals have more valence electrons (less tendency to lost electrons)
Explain reactivity of metals, and its trend.
Measures how readily an element will lose electrons.
INCREASES DOWN GROUP + DECREASES ACROSS PERIOD
- weaker electrostatic attraction: more easily electrons are lost
Explain reactivity of non-metals, and its trend.
Measures how readily a non-metal atom will accept an electron.
DECREASES DOWN GROUP + INCREASES ACROSS PERIOD
