Precipitate Reactions
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Precipitate Reactions
Hi! I need help determining if a reaction will produce a precipitate, gas or no reaction...also how to determine whether a compound is a gas, liquid, solid, or aqueous.
THANKS!
Well you will need to rememorize your solubility rules.
http://www.sparknotes.com/testprep/book ... ion3.rhtml
Most alkali metal compounds and compounds are soluble.
Cl-, Br-, I- compounds are soluble, except when they contain Ag+, , or Pb2+.
F- compounds are soluble, except when they contain group 2A metals.
, , , and CH3COO- compounds are soluble.
compounds are soluble, except when they include Ca2+, Sr2+, Ba2+, Ag+, Pb2+, or .
, , , , S2-, OH-, and O2- compounds are insoluble.
Group 2A metal oxides are classified as strong bases even though they are not very soluble.
The two solubility rules that you will use the most are numbers 1 and 4. You must memorize that all group 1A metal and ammonium compounds are soluble. As soon as you see a compound , Li, Na, K, Rb, Cs, or Fr, you should know that it’s soluble. Also, all nitrates are soluble—look at the end of the compound. If it ends in , you know that it’s soluble.
What’s the big deal with solubility? Well, if the ion is soluble, it won’t form a precipitate, and this means it doesn’t react and should be left out of the net ionic equation. The key is first to write the compound’s chemical formula and then determine if it’s soluble. If it is soluble, then ionize it—if it isn’t, don’t ionize it; leave it as a molecule.
Here are some additional rules about common reaction types that you should be familiar with for the exam:
If an insoluble precipitate or gas can be formed in a reaction, it probably will be.
Oxides (except group 1A) are insoluble, and when reacted with water, they form either acids (nonmetal oxides) or bases (metal oxides).
There are six strong acids that completely ionize: HCl, HBr, HI, HNO3, H2SO4, HClO4. All other acids are weak and are written together, as molecules.
The strong bases that ionize are oxides and hydroxides of group 1A and 2A metals. All other oxides and hydroxides are considered weak and written together, as molecules.
http://www.sparknotes.com/testprep/book ... ion3.rhtml
Most alkali metal compounds and compounds are soluble.
Cl-, Br-, I- compounds are soluble, except when they contain Ag+, , or Pb2+.
F- compounds are soluble, except when they contain group 2A metals.
, , , and CH3COO- compounds are soluble.
compounds are soluble, except when they include Ca2+, Sr2+, Ba2+, Ag+, Pb2+, or .
, , , , S2-, OH-, and O2- compounds are insoluble.
Group 2A metal oxides are classified as strong bases even though they are not very soluble.
The two solubility rules that you will use the most are numbers 1 and 4. You must memorize that all group 1A metal and ammonium compounds are soluble. As soon as you see a compound , Li, Na, K, Rb, Cs, or Fr, you should know that it’s soluble. Also, all nitrates are soluble—look at the end of the compound. If it ends in , you know that it’s soluble.
What’s the big deal with solubility? Well, if the ion is soluble, it won’t form a precipitate, and this means it doesn’t react and should be left out of the net ionic equation. The key is first to write the compound’s chemical formula and then determine if it’s soluble. If it is soluble, then ionize it—if it isn’t, don’t ionize it; leave it as a molecule.
Here are some additional rules about common reaction types that you should be familiar with for the exam:
If an insoluble precipitate or gas can be formed in a reaction, it probably will be.
Oxides (except group 1A) are insoluble, and when reacted with water, they form either acids (nonmetal oxides) or bases (metal oxides).
There are six strong acids that completely ionize: HCl, HBr, HI, HNO3, H2SO4, HClO4. All other acids are weak and are written together, as molecules.
The strong bases that ionize are oxides and hydroxides of group 1A and 2A metals. All other oxides and hydroxides are considered weak and written together, as molecules.