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[From: ] [author: ] [Date: 12-05-15] [Hit: ]
K2NO3, AgNO3,CaCl2 + K2CO3?Choices - CaCO3, CO2, CaCl2,......
For each of the following proposed reactions, in aqueous solution, choose the precipitated product.


KCl + AgNO3 ?
Choices - AgCl, K2NO3, AgNO3, Ag

CaCl2 + K2CO3 ?
Choices - CaCO3, CO2, CaCl2, KCl

SrCl2 + K2SO4 ?
Choices - K2SO4, Sr, SrSO4, KSO4

KNO3 + AgCl ?
Choices - AgCl, KCl, K2CO3, K2NO3

Or if none of them work, "No observed reaction" is possible. Thanks!

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Memorize these rules: http://www.csudh.edu/oliver/chemdata/sol…

KCl + AgNO3 ?
Choices - AgCl, K2NO3, AgNO3, Ag
Chlorides are soluble except Ag....

CaCl2 + K2CO3 ?
Choices - CaCO3, CO2, CaCl2, KCl
carbonates are generally not soluble (marble is CaCO3)

SrCl2 + K2SO4 ?
Choices - K2SO4, Sr, SrSO4, KSO4
Sulfates are soluble except for Sr....

KNO3 + AgCl ?
Choices - AgCl, KCl, K2CO3, K2NO3
No reaction. The AgCl is not soluble. Chlorides are soluble except Ag....

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These are double displacement reactions.
The formula is AB+CD ---> AD + CB

A & C are positive ions, B & D are negative. You have to match pos with neg in the proper amount by charge.

KCl + AgNO3 ---> KNO3 + AgCl
A.B + C...D makes A..D + C...B
luckily, NO3 carries a -1 charge to balance K's +1 charge, so they are equal. Ag, a transition metal can be +1 or +2, depending on what it's bonded with. Cl is -1, so they are balanced as well.
To see what phase they are in, use http://www.ptable.com
in the middle hit "State at 273K" after clicking on PROPERTIES on the upper left.
put the mouse over each element -- for example K is a solid but N and O are gases. However, to bond with a solid, NO3- must become solid. Therefore KNO3 is a solid. Same with AgCl. Ag is a solid, but Cl is a gas. A solid and a gas cannot mix, one has to change phase. The gas will always become solid in this case.

So you would know for this one, of those choices, only AgCl is made, just by looking at the stoichiometry.
Ag is elemental silver -- it's not made by this reaction, AgNO3 is a reactant, not a product, and K2NO3 is not a balanced compound, because NO3 is -1, and K is +1, therefore K2NO3 would have a +1charge! All compounds attempt to go to a ZERO charge when bonding.

Good luck!
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