Define the term transition element.
Sketch the form of a $3d_{z^2}$ orbital.
Explain the meaning of a heterogeneous catalyst.
Describe how a heterogeneous catalyst works in a reaction.
Write equations for both reactions described below. Reaction 1: Manganese(VII) oxide, $\text{Mn}_2\text{O}_7$, is formed when $\text{KMnO}_4$ is treated with concentrated sulfuric acid. Reaction 2: $\text{Mn}_2\text{O}_7$ breaks down to give manganese(IV) oxide and a colourless diatomic gas.
Write the ionic equation, and state the type of reaction, for the reaction of $[\text{Mn(H}_2\text{O})_6]^{2+}$ with $\text{NaOH}(aq)$.
Write the ionic equation, and state the type of reaction, for the reaction of $[\text{Mn(H}_2\text{O})_6]^{2+}$ with concentrated $\text{HCl}$.
Suggest the formula of the manganese species formed when $\text{Mn}^{2+}(aq)$ reacts with $\text{Cl}_2$. State the reaction type.