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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)

A first-order chemical reaction is observed to have a rate constant of 32 min –1. What is the corresponding half-life for the reaction? (1 min = 60s) This question requires calculations in submitted scratch paper.

The following equation is known as ________ law: .