General Chemistry 2

Find the concentration of HS$^-$, S$^{2-}$ and H$_3$O$^+$ in a 0.075 M solution of H$_2$S

H$_2$S + H$_2$O $\longrightarrow$ HS$^-$ + H$_3$O$^+$, K$_{a1}$ = 1.0 x 10$^{-7}$

HS$^-$ + H$_2$O $\longrightarrow$ S$^2-$ + H$_3$O$^+$, K$_{a2}$ = 1.0 x 10$^{-19}$

Calculate the pH and concentration of all species of a 3.0 M solution of phosphoric acid, H$_3$PO$_4$

Find the equilibrium concentrations of the species H$_2$SO$_4$, HSO$_4^-$, SO$_4^{2-}$, and H$^{+}$ given a 1.0 M solution of H$_2$SO$_4$.

Find the pH of the buffer solution consisting of 0.60 M HF and 1.0 M KF (K$_a$ of HF = 7.2 x 10$^{-4}$)

A buffer solution consisting of 0.60 M HF and 1.0 M KF (Ka of HF = 7.2 x 10$^-4$) is titrated by 0.2 mol HCl. After the HCl is added, there is 1 L of solution. Find the pH of the solution.

Find the pH of the buffer solution consisting of 0.100 M HONH$_2$ and 0.100 M HONH$_3^+$ (K$_b$ of HONH$_2$ = 1.1 x 10$^{-8}$), after .02 moles HCl is added to the buffer solution? (assume the final volume of the solution is 1 L)

10.00 mL of an unknown H$_2$CO$_3$ solution is titrated with 0.0500 M NaOH and it requires 15.67 mL to reach the end point. What is the concentration of the H$_2$CO$_3$ ?

H$_2$CO$_3$ + 2 NaOH $\longrightarrow$ Na$_2$CO$_3$ + 2 H$_2$O

Sketch the titration curve for 50.0 mL 0.1 M CH$_3$COOH, K$_a$ = 1.8 x 10$^{-5}$ with 0.1 M NaOH. Include points on your graph and an example calculation for the initial pH, the pH at half way to the equivalence point, the pH at the equivalence point and the pH after the equivalence point.

By experiment, it is found that of 6.2 x 10$^{-12}$ moles of Pb$_3$(PO$_4$)$_2$ dissolves in 1 L of aqueous solution at 25$^\circ$C. What is the solubility product constant, K$_{sp}$, at this temperature?

The solubility of Ce(IO$_3$)$_3$ in a 0.20 M KIO$_3$ solution is 4.4 x 10$^{-8}$ mol/L. Calculate K$_{sp}$ for Ce(IO$_3$)$_3$.

Calculate the concentrations of Ag$^+$, Ag(S$_2$O$_3$)$^-$, and Ag(S$_2$O$_3$)$_2^{3-}$ in a solution prepared by mixing 150.0 mL of 1.00 x 10$^{-3}$ M AgNO$_3$ with 200.0 mL of 5.00 M Na$_2$S$_2$O$_3$. The stepwise formation equilibria are:

Ag$^+$ + S$_2$O$_3^{2-}$ $\leftrightharpoons$ Ag(S$_2$O$_3$)$^-$ K$_{f1}$ = 7.4 x 10$^{8}$

Ag(S$_2$O$_3$)$^-$ + S$_2$O$_3^{2-}$ $\leftrightharpoons$ Ag(S$_2$O$_3$)$_2^{3-}$ K$_{f2}$ = 3.9 x 10$^{4}$

N$_2$ (g) + 3 H$_2$ (g) $\leftrightharpoons$ 2 NH$_3$ (g)

For the reaction above what is $\triangle$H$^\circ$ given that $\triangle$H$_f^\circ$ for NH$_3$ (g) is -45.9 kJ/mol at 25$^\circ$C?

Calculate the standard free energy change, $\triangle$G$^\circ$, for the following reaction. Is the reaction spontaneous?

CH$_4$ (g) + 2 O$_2$ (g) $\longrightarrow$ CO$_2$ (g) + 2 H$_2$O (l)

Values of standard molar entropy, S$_{f}^\circ$ are as follows: CH$_4$ (g), 186 J/(K*mol); O$_2$ (g), 205 J/(K*mol); CO$_2$ (g), 213.6 J/(K*mol); 2 H$_2$O (l), 69.9 J/(K*mol)

$\triangle$H$^\circ$ for this reaction is -890.3 kJ

The following reaction takes place under acidic conditions. Assign oxidation numbers and balance the oxidation reduction reaction using the half reaction method.

HNO$_3$ + Fe$^{2+}$ $\longrightarrow$ Fe$^{3+}$ + NO$_2$

Balance the following redox reaction given acidic conditions, using the half reaction method.

$S (s) + NO_2^+ (aq) \longrightarrow SO_2^- (aq) + NO (g)$ .

What is the standard free energy change, $\triangle G ^\circ$ for the following reaction at 25$^\circ$

$Cu ^{2+} (aq) + Fe (s) \longrightarrow Cu (s) + Fe ^{2+} (aq)$

What is the atomic notation for the element Fe?