Physical Chemistry & Transition Elements Random Retrieval

Salt bridges are required for a cell E^ϴcell/V to be measured.

What statement best describes the action of a salt bridge?

The compound with the formula K₃[Fe(CN)₆]

(i) is potassium hexacyanoferrate(III)

(ii) contains a complex with an octahedral shape

(iii) includes iron in the oxidation state +3

(iv) contains an hexadentate ligand

Which first-row d-block element is used as the catalyst for the addition of hydrogen gas to C=C double bonds?

Which metal forms aqueous ions in the +2 state which precipitate as a hydroxide on adding ammonia solution and redissolve to form a deep blue solution

Calculate the value of the enthalpy change associated with the following equation?

3Rb_(g)=> 3Rb_(s)

What enthalpy change is represented by the following equation?

Ca_(s) => Ca_(g)

What is the enthalpy of solution of lithium bromide given that:

the lattice enthalpy for LiBr = -818 kJ mol^-1

enthalpy of hydration of Li⁺ ions = -559 kJ mol^-1

enthalpy of hydration of Br^- ions = -309 kJ mol^-1

pH = 2.9 for a solution which contains equal concentrations of chlorethanoic acid and sodium chlorethanoate. What is the pH of the solution after mixing it with twice its own volume of pure water?

Consider the following equilibrium:

PCl_3(g) + Cl_2(g) <=> PCl_5(g)

6.00 mol of PCl₃was mixed with 6.00 mol of Cl₂ and the mixture sealed in a vessel and allowed to reach equilibrium. At equilibrium, 2.00 mol of PCl₅ was present in the equilibrium mixture.

Calculate the value of the mole fraction of PCl₅ present in the mixture under these conditions.

An alloy of platinum with rhodium is the catalyst used:

(i) in catalytic converters to cut pollution from motor vehicles

(ii) in the synthesis of ammonia from nitrogen and hydrogen

(iii) in the oxidation of ammonia to NO_(g) during the manufacture of nitric acid

(iv) in the hydrogenation of vegetable oils.