Chemistry chapters 8, 9, 10, 11

• electrons are transferred
• metals react with nonmetals
• ions paired have lower energy (greater stability) than separated ions

• E= units in joules
• r = distance between ion centers in nanometers
• Q1 and Q2 = numerical ion charges 

to find the energy of interaction between a pair of ions

electrons are shared by a nuclei 

• also called non polar covalent
• when electrons are shared evenly 

when electrons are shared unequally 

 across a period from left to right 

down a group

larger because they are more negative with more electrons

smaller because they are more positive with less electrons 

down; right to left 

the change in energy that takes p;ace when separated gaseous ions are packed  together to form an ionic solid 

M⁺  (g) + X^- (g) --> MX (s)

the energy change is exothermic (negative) 

• 
• k = constant dependent on the solid structure and electron configuration 
• Q1 and Q2 are charges of the ions 
• r = shortest distance between centers of the cations and the anions  

increases; increases; decreases 

1.6 

shortens 

deltaH = sum of the energies required to break old bond (endothermic) + sum of the energies released in formong new bonds (exothermic) 

• 
• D is always positive 
• D = bond energy per mole of bonds 

hydrogen, lithium, berylium, and boron 

second row elements 

104.5 

109.5

107