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victoria-hubbard
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Chemists believe that many chemical compounds contain ions
Common Properties of these compounds:◦High melting point (ex: salt melt at 800*C)
◦Tightly packed structure (Crystal Lattice)
◦As a solid does not conduct but when melted is a good conductor
◦Pure water does not conduct electricity but when the cmpd is dissolved in water, the solution conducts electricity.
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The arrangement of sodium ions
(Na+) and chloride ions (Cl-) in the ionic compound sodium chloride.
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(a) Pure water does not conduct a current; (b) Water containing a dissolved salt conducts electricity
A substance containing ions that can move can conduct electric current
Dissolving salt (NaCl) causes ions to be dispersed in the water move freely
Some substances dissolve in water to form a solution that conducts well - these are called electrolytes
When dissolved in water, electrolyte compounds break up into component ions
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Ionic compounds – a compounds formed between a metal and a nonmetal
An ionic compounds must contain a net charge of ZERO
Must be composed of anions AND cations
Total charge of cations + total charge of anions = Zero net
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Na+ and Cl- NaClCharge (+1) and (-1) net 0
Mg2+ and Cl- Cation (+2) and Anion (-1)Need 2 anions (-2) for Net 0 charge
Lithium and Nitrogen8
ions that have a positive charge are called cations◦form when an atom loses electrons
ions that have a negative charge are called anions ◦form when an atom gains electrons
ions with opposite charges attract ◦therefore cations and anions attract each
other moving ions conduct electricity compound must have no total charge, therefore
we must balance the numbers of cations and anions in a compound to get 0 total charge
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