Untitled - Kelly Walsh High School

62 CHEMISTRY FOR THE UTTERLY CONFUSED
Quick Tip
LiF(aq) H 2SO 4(aq) l Li 2SO 4 HF
(Li and F with H and SO 4 2 ) l (Li and SO4 2 with H and F )
There is one complication in these results. The compound carbonic acid,
H 2CO 3, is unstable in water. It will rapidly decompose to gaseous carbon dioxide
and liquid water. Therefore, we should replace H 2CO 3 with CO 2 H 2O.
Some instructors will accept H 2CO 3 as the product. You should check with your
instructor to see how you should write the product of this reaction.
We can now balance each reaction by inspection:
Cr(OH) 3(s) 3 HClO4(aq) l Cr(ClO4) 3 3 H2O 3 KCl(aq) (NH4) 3PO4(aq) l K3PO4 3 NH4Cl Na2CO3(aq) 2 HCl(aq) l 2 NaCl H2CO3 Mg(NO3) 2(aq) Ca(OH) 2(aq) l Mg(OH) 2 Ca(NO3) 2
2 HNO3(aq) Ba(OH) 2(aq) l Ba(NO3) 2 2 H2O 2 LiF(aq) H2SO4(aq) l Li2SO4 2 HF
These are the balanced molecular equations. We have omitted the phase designations
in order to enhance the readability in this book. In generally, you should
use them.
We now need to separate all the strong electrolytes into their component ions.
We may begin with any category of strong electrolyte. In these examples, we
will begin with the strong acids. Below each of the strong acids, we will write
the separated ions:
Cr(OH) 3(s) 3 HClO 4(aq) l Cr(ClO 4) 3 3 H 2O
3 H 3 ClO 4
3 KCl(aq) (NH4) 3PO4(aq) l K3PO4 3 NH4Cl Na2CO3(aq) 2 HCl(aq) l 2 NaCl CO2 H2O 2 H 2 Cl