Calculate whether or not a precipitate will form if 1.30 mL of 0.80 M NH3 are added to 2.2 L of 1.0 10-3 M FeSO4. Calculate Q.
So what is your problem in calculating Q?.
To determine whether or not a precipitate will form, we need to calculate the reaction quotient (Q) and compare it to the solubility product constant (Ksp) of the reaction. If Q is greater than Ksp, a precipitate will form. If Q is less than or equal to Ksp, no precipitate will form.
The balanced equation for the reaction between NH3 and FeSO4 is:
FeSO4 + 2NH3 → Fe(NH3)2SO4
First, we need to determine the moles of NH3 and FeSO4 present in the given volumes and concentrations:
moles of NH3 = volume of NH3 (in L) x concentration of NH3
= 1.30 mL x (1 L / 1000 mL) x 0.80 M
= 0.00104 moles
moles of FeSO4 = volume of FeSO4 (in L) x concentration of FeSO4
= 2.2 L x 1.0 x 10^(-3) M
= 0.0022 moles
Since the stoichiometry of the reaction is 1:2 between FeSO4 and NH3, we need to compare the moles of NH3 to half the moles of FeSO4:
moles of NH3 / (moles of FeSO4 / 2)
= 0.00104 / (0.0022 / 2)
= 0.00104 / 0.0011
= 0.945
Now, we can calculate the reaction quotient (Q) using the concentrations of the species at equilibrium:
Q = [Fe(NH3)2SO4] / ([NH3]^2 * [FeSO4])
= 0.945 / (0.80^2 * 1.0 x 10^(-3))
= 1.48 x 10^3
Therefore, the reaction quotient (Q) is 1.48 x 10^3. To determine whether or not a precipitate will form, we need to compare Q to the solubility product constant (Ksp) of Fe(NH3)2SO4. If Q is greater than Ksp, a precipitate will form. If Q is less than or equal to Ksp, no precipitate will form.