Predict whether reactions should occur between aqueous solutions of the following compounds. If so, write balanced molecular and net ionic equations for the reactions. Include physical states.
a. (NH4)2CO3 and CrCl3
b. Ba(OH)2 and HCl
c. FeCl3 and NaOH
d. Ca(HCO3)2 and HNO3
You need to know solubility rules for this question. Here is a simplified set of rules. Memorize them.
http://www.files.chem.vt.edu/RVGS/ACT/notes/solubility_rules.html
a. Reactions occur between (NH4)2CO3 and CrCl3 because (NH4)2CO3 is a soluble salt and CrCl3 is also a soluble salt.
The balanced molecular equation is:
(NH4)2CO3(aq) + CrCl3(aq) -> 2NH4Cl(aq) + CrCO3(s)
The balanced net ionic equation is:
2NH4+(aq) + CO3^2-(aq) + 3Cr^3+(aq) + 3Cl^-(aq) -> 2NH4+(aq) + 3Cl^-(aq) + CrCO3(s)
b. Reactions occur between Ba(OH)2 and HCl because Ba(OH)2 is a soluble salt and HCl is a strong acid.
The balanced molecular equation is:
Ba(OH)2(aq) + 2HCl(aq) -> BaCl2(aq) + 2H2O(l)
The balanced net ionic equation is:
Ba^2+(aq) + 2OH^-(aq) + 2H+(aq) + 2Cl^-(aq) -> Ba^2+(aq) + 2Cl^-(aq) + 2H2O(l)
c. Reactions occur between FeCl3 and NaOH because FeCl3 is a soluble salt and NaOH is a strong base.
The balanced molecular equation is:
FeCl3(aq) + 3NaOH(aq) -> Fe(OH)3(s) + 3NaCl(aq)
The balanced net ionic equation is:
Fe^3+(aq) + 3OH^-(aq) + 3Na+(aq) + 3Cl^-(aq) -> Fe(OH)3(s) + 3Na+(aq) + 3Cl^-(aq)
d. Reactions occur between Ca(HCO3)2 and HNO3 because Ca(HCO3)2 is a soluble salt and HNO3 is a strong acid.
The balanced molecular equation is:
Ca(HCO3)2(aq) + 2HNO3(aq) -> Ca(NO3)2(aq) + 2H2O(l) + 2CO2(g)
The balanced net ionic equation is:
Ca^2+(aq) + 2HCO3^-(aq) + 2H+(aq) + 2NO3^-(aq) -> Ca^2+(aq) + 2NO3^-(aq) + 2H2O(l) + 2CO2(g)
To predict whether reactions should occur between aqueous solutions of compounds, we need to check if there will be any possible precipitate formation or acid-base reactions. Let's go through each compound combination one by one:
a. (NH4)2CO3 and CrCl3
To determine if a reaction will occur between (NH4)2CO3 and CrCl3, we need to check if there will be a precipitation reaction. We can do this by examining the solubility rules. Based on the solubility rules, (NH4)2CO3 is soluble while most chlorides are soluble except for those of Ag+, Pb2+, and Hg2+.
Therefore, (NH4)2CO3 and CrCl3 will react to form a precipitate, which is CrCO3.
The balanced molecular equation is:
(NH4)2CO3(aq) + CrCl3(aq) → (NH4)2CrCO3(s) + 3NH4Cl(aq)
The net ionic equation is:
CO3^2-(aq) + Cr^3+(aq) → CrCO3(s)
b. Ba(OH)2 and HCl
To determine if a reaction will occur between Ba(OH)2 and HCl, we need to check if there will be an acid-base reaction. Ba(OH)2 is a strong base, and HCl is a strong acid.
Therefore, Ba(OH)2 and HCl will react to form water and a salt, which is BaCl2.
The balanced molecular equation is:
Ba(OH)2(aq) + 2HCl(aq) → 2H2O(l) + BaCl2(aq)
The net ionic equation is:
Ba^2+(aq) + 2OH^-(aq) + 2H^+(aq) + 2Cl^-(aq) → 2H2O(l) + Ba^2+(aq) + 2Cl^-(aq)
c. FeCl3 and NaOH
To determine if a reaction will occur between FeCl3 and NaOH, we need to check if there will be a precipitation reaction. Based on the solubility rules, FeCl3 is soluble while hydroxides of most metals except those of Group 1A (Li+, Na+, K+, etc.) and ammonium (NH4+) are insoluble.
Therefore, FeCl3 and NaOH will react to form a precipitate, which is Fe(OH)3.
The balanced molecular equation is:
FeCl3(aq) + 3NaOH(aq) → 3NaCl(aq) + Fe(OH)3(s)
The net ionic equation is:
Fe^3+(aq) + 3OH^-(aq) → Fe(OH)3(s)
d. Ca(HCO3)2 and HNO3
To determine if a reaction will occur between Ca(HCO3)2 and HNO3, we need to check if there will be an acid-base reaction. Ca(HCO3)2 contains the bicarbonate ion (HCO3^-), which can act as a weak acid. HNO3 is a strong acid.
Therefore, Ca(HCO3)2 and HNO3 will react in an acid-base reaction to form water and a salt, which is Ca(NO3)2.
The balanced molecular equation is:
Ca(HCO3)2(aq) + 2HNO3(aq) → 2H2O(l) + Ca(NO3)2(aq) + 2CO2(g)
The net ionic equation is:
HCO3^-(aq) + 2H^+(aq) → 2H2O(l) + CO2(g)
Remember to include the physical states in the equations (aq for aqueous, s for solid, l for liquid, and g for gas) to make them complete.