7.5 Electrolytes Flashcards
what are non-electrolytes
molecules which remain together when dissolved are non-electrolytes and are called covalent solution or compound solutions
What makes a compound a non-electrolyte
Molecular solutions aka covalent solutions do not form charged particles (ions), there is nothing to conduct electrons through the solution and no current flows.
If a compound’s formula does NOT contain a metal or NH4you can be confident it is a non-electrolyte.
What happens when ionic compounds dissolve
When ionic compounds dissolve, they do not remain as molecules but split up into ions
What can strong electrolytes do
Strong electrolytes carry currents because the positive ions can accept electrons, and the negative ions can donate electrons to complete the circuit
Mobile Ions are necessary to create an electrolyte.
What is dissociation, cations and anions
The breaking up of an ionic structure into its ions as it dissolves is called dissociation.
Positive ions are called cations and negative ions are called anions.
What happens when ionic compounds dissolve slightly
When some ionic compounds dissolve only to a slight extent, we say they have low-solubility, not all the molecules break up into ions. In fact, relatively few do. The equation would still be written:
AB(s)→ A+(aq) + B-(aq)
since most of the solute is still a compound there are less ions to carry a current
What do we call slightly ionized compounds
Ionic compounds which ionize only partially are called weak electrolytes. Some examples of weak electrolytes are acetic acid (HC2H3O2), oxalic acid (H2C2O4), and ammonia, (NH3).
What are strong electrolytes
Strong Electrolytes
Example: A highly ionic AND highly soluble compound
Ca(NO3)2(s) → Ca +2(aq) + 2 NO3 -1(aq)
What are weak electrolytes
Weak Electrolytes
Example 1: A low solubiility ionic compound which dissociates very slightly.
CaCO3(s) → Ca 2+(aq) + CO3 2-(aq)
Example 2: A high solubility covalent compound that ionizes only slightly
NH3(g) + H2O(l) → NH4 +1(aq) + OH -1(aq)
What are non-electrolytes
Non-electrolytes
Example: A covalent compound that has very very low ionization.
C6H12O6(s) → C6H12O6(aq)
What determine ionic and covalent bonding
Ionic or covalent bonding is dependent on the electronegativity difference between atoms. If that difference is high enough, electrons are likely to be transferred and the bond is considered “ionic”. In a large molecule, ifanybond is ionic, the entire compound is considered to be ionic.
Why is NaCl ionic
The NaCl is ionic, but there are trillions upon trillions of bonds in the crystal. Not all of the bonds will be ionic. It does have a very high “percent ionic character”, meaning it is mostly ionic. When it dissolves it produces mostly charged particles
how else can you make electrolytes
You can also create a strong electrolyte by melting an ionic compound! However this requires VERY high temperatures!
What kind of compound would have a small percent ionic character
Now consider a large clear crystal of citric acid (H3C6H5O7). It is mostly covalent, but does have a small “percent ionic character”. It is highly soluble in water so it can make a highly concentrated solution, but mostly it stays as discreet, covalent molecules of citric acid which areNOTcharged particles. This solution is aWeak Electrolytebecause although the compound is highly soluble it has a low ionic character.
