CH1012
L1 /
‹#›
L1 /
10
RADII AND IE1- GROUPS
• the atomic and ionic radii within each group increase down the group because of the greater number of
electron shells that accompany the increase in atomic number.
Zeff (effective nuclear charge) remains essentially constant on descending a group.
Zeff (effective nuclear charge) remains essentially constant on descending a group.
• Ionisation energies (IE1): M(g) ® M+(g) + e-decrease
going down the group, the atoms get larger & so
the outermost electrons are further from the attractive nuclear
charge.
meaning it takes less energy to eject them.
meaning it takes less energy to eject them.
• (N.B. for Groups 3 & 4
the lowest element in the group has a slightly higher IE1 than the previous
one due to lanthanide contraction)
