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The standard reduction potentials are as follows: Cr3+(aq) + 3 e– → Cr(s);  E° = –0.74 V Pb2+(aq) + 2 e– → Pb(s);  E° = –0.13 V Calculate the standard Gibbs free energy change for the following reaction. 2 Cr(s) + 3 Pb2+ → 3 Pb(s) + 2 Cr3+(aq) Written work required

A sample of methane, CH 4, occupies a volume of 350.0 mL at 25°C and exerts a pressure of 1140.0 mmHg. If the volume of the gas is allowed to expand to 500.0 mL at 298 K, what will be the pressure of the gas? Written work required

What volume of a 0.850 M solution of CaCl 2 contains 1.28 g of solute? Written work required

A solution has a hydroxide ion concentration of 0.0080  M. Calculate the pOH of the solution at 25 °C. ( K w = 1.01 × 10 –14) Written work required

Consider the following equilibrium. PCl3(g) + Cl2(g) PCl5(g)      ΔH = –92 kJ  The concentration of PCl3 at equilibrium can be increased by: Hint: Is the reaction endothermic or exothermic? Based on this, determine the shift needed to reach equilibrium and what can cause that shift

Below is a proposed mechanism for the decomposition of H 2O 2. H2O2 + I– → H2O + IO– slow H2O2 + IO– → H2O + O2 + I– fast Which of the following statements is incorrect?

Elementary steps in a reaction mechanism often include reaction _____. These (usually) short-lived species, which are at one point produced and then later consumed, do not appear in the overall chemical reaction.

At a given temperature, K = 0.024 for the equilibrium: PCl5(g)    PCl3(g) + Cl2(g) What is K for: Cl2(g) + PCl3(g)    PCl5(g)? This problem requires calculations on submitted scratch paper. Hint: Determine mathematical relationship of both chemical equations to determine new value of K

Which of the given relationships correctly compares the rates of the reactants and products for the reaction below? 2 NOCl(g) → 2 NO(g) + Cl2(g)

Given the following equilibria,   Ni2+(aq) + 2 OH–(aq) Ni(OH)2(s) K1 = 1.8 × 1015   Ni2+(aq) + 4 CN–(aq) Ni(CN)42–(aq) K2 = 2.0 × 1031 determine the equilibrium constant, Kc, for the following reaction.Ni(OH)2(s) + 4 CN–(aq) Ni(CN)42–(aq) + 2 OH–(aq)