The stoichiometric equation for the oxidation of bromide ions by hydrogen peroxide in acid solutions is 2 Br– + H2O2 + 2 H+ → Br2 + 2 H2O ? = ?[H2O2][H+][Br−] If the concentration of H2O2 is increased by a factor of three, by what factor is the rate of consumption of Br– ions increased

Substances that poison a catalyst pose a major concern for many engineering designs, including those for catalytic converters. One design option is to add materials that react with potential poisons before they reach the catalyst. Among the commonly encountered catalyst poisons are silicon and phosphorus, which typically form phosphate or silicate ions in the oxidizing environment of an engine. Group 2 elements are added to the catalyst to react with these contaminants before they reach the working portion of the catalytic converter. If estimates show that a catalytic converter will be exposed to 625 g of silicon during its lifetime, what mass of beryllium would need to be included in the design?

Which reaction mechanism assumptions are unimportant in describing simple ionic reactions between cations and anions? Why?

Hydrogen peroxide decomposes to water and oxygen gas more rapidly when manganese dioxide is added. The manganese dioxide is not consumed in the reaction. Explain the role of the manganese dioxide.

The direct reaction of iron(III) oxide. Fe2O3, to give iron and oxygen gas is a nonspontaneous reaction; normally, iron combines with oxygen to give rust (the oxide). Yet we do change iron(III) oxide, as iron ore, into iron metal. How is this possible? Explain.

. Suppose that for the reaction 2N2O(g)+O2(g)4NO((g))it is determined, at a particular temperature, that the equilibrium concentrations arc [NO(g)]=0.00341M,[N2O(g)]=0.0293M, and [O2(g)]=0.0325M. Calculate the value of K for the reaction at this temperature.

. What does the activation energy for a reaction represent? How is the activation energy related to whether a collision between molecules is successful?

Determine rxnH 25 C for the following reaction: NO g O2 g NO2 g This reaction is a major participant in the formation of smog.

What is the role of the activated complex in a chemical reaction?

One of the concerns about the use of Freons is that they will migrate to the upper atmosphere, where chlorine atoms can be generated by the following reaction: CCl2F2(g)Freon-12hvCF2Cl(g)+Cl(g) Chlorine atoms can act as a catalyst for the destruction of ozone. The activation energy for the reaction Cl(g) + O3(g) ClO(g) + O2(g) Is 2.1 kJ/mol. Which is the more effective catalyst for the destruction of ozone, Cl or NO? (See Exercise 75.)