Physical Chemistry & Transition Elements Random Retrieval

For this question, look at the resource, ‘A Selection of Standard Electrode Potentials’ (‘A Selection of Standard Electrode Potentials’can be found in TOOLS>Data Sheets)

When nitric(V)acid is added to a purple solution of V²⁺_(aq) ions and the mixture allowed to stand for a few minutes, what colour will be observed in the solution?

Thinking carefully about the definitions of anode and cathode in electrochemical cells, an anode is defined as (CARE!):

Using your half-equations from questions 4 & 5, balance the REDOX equation below.

BrO₃^- + H⁺ + C₂O₄^2- => CO₂ + Br^- + H₂O

Select the integers that represent the ratio of species in the overall balanced REDOX equation.

If this question appears in a Random Retrieval quiz, you would be best constructing separate half-equations for the species that is oxidised and the species that is reduced prior to working out the overall REDOX equation.

Using oxidation numbers (states) work out the ratio of the species in the following half-equation.

S₂O₃^2- + H₂O => SO₄^2- + H⁺ + e^-

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

Which first-row d-block element has the electron configuration

1s²2s²2p⁶3s²3p⁶4s¹3d⁵?

What enthalpy change is represented by the following equation?

S^-_(g) + e^-=> S^2-_(g)

What is the hydrogen ion concentration in an aqueous solution if the pH = 3.0?

Consider the following equilibrium for the reaction that generates hydrogen for use in the Haber-Bosch Process:

CH_4(g) + H₂O_(g) <=>CO_(g) + 3H_2(g)

140 mol of CH₄ was mixed with 100 mol of H₂O and the mixture given time to reach equilibrium. At this point, 240 mol of H₂ was present in the mixture.

Calculate the value of the mole fraction of CH₄ present in the mixture under these conditions.

By inspection of this experimental data, what is the rate equation for this reaction?