CHE 105/110 Introduction to Chemistry - Exercises and Answers

1.

Describe the three parts of an ICE chart.

1.

     I = initial concentrations;

    C = change in concentrations;

    E = equilibrium concentrations

3.

$$\begin{array}{ccc}3{\text{O}}_2\text{(g)}& \rightleftarrows & 2{\text{O}}_3\text{(g)}\\ 0.075\text{ M}& & \end{array}$$

3.

5.

$$\begin{array}{ccccccc}{\text{CH}}_{\text{4}}\text{(g)}& +& {\text{2O}}_{\text{2}}\text{(g)}& \rightleftarrows & {\text{CO}}_{\text{2}}(\text{g})& +& {\text{2H}}_{\text{2}}\text{O(}\ell \text{)}\\ 0.0060\text{M}& & 0.05\text{5}\text{M}& & & & \end{array}$$

5.

7.

$$\begin{array}{c}\text{HCN(g)}\\ 2.00\text{M}\end{array}\begin{array}{c}\rightleftarrows \\ \end{array}\begin{array}{c}\text{HNC(g)}\\ \end{array}\begin{array}{c}{K}_{\text{eq}}=4.50\\ \end{array}$$

7.

[HCN] = 0.364 M; [HNC] = 1.64 M

9.

Determine the equilibrium concentrations for this chemical reaction with the given K_eq.

$$\begin{array}{c}{\text{N}}_{\text{2}}{\text{O}}_3(\text{g})\\ 0.0663\text{M}\end{array}\begin{array}{c}\rightleftarrows \\ \end{array}\begin{array}{c}\text{NO(g)}\\ \end{array}\begin{array}{c}+\\ \end{array}\begin{array}{c}{\text{NO}}_{\text{2}}\text{(g)}\\ \end{array}\begin{array}{c}{K}_{\text{eq}}=2.50\\ \end{array}$$

9.

[N₂O₃] = 0.0017 M; [NO] = [NO₂] = 0.0646 M

11.

Determine the equilibrium concentrations for this chemical reaction with the given K_eq.

$$\begin{array}{c}{\text{H}}_{\text{2}}\text{S(g)}\\ 0.882\text{M}\end{array}\begin{array}{c}\rightleftarrows \\ \end{array}\begin{array}{c}{\text{H}}_{\text{2}}\text{(g)}\\ \end{array}\begin{array}{c}+\\ \end{array}\begin{array}{c}\text{S(s)}\\ \end{array}\begin{array}{c}{K}_{\text{eq}}=0.055\\ \end{array}$$

11.

[H₂S] = 0.836 M; [H₂] = 0.046 M