The shorthand electronic configuration of cobalt is $[\text{Ar}]3d^74s^2$. Identify what $[\text{Ar}]$ means by giving the full electronic configuration.
The electrons with the lowest energy in cobalt occupy the $1s$ orbital. Sketch the form of a $1s$ orbital.
Deduce how many unpaired electrons are present in a cobalt atom.
Table 1.1 provides details of the stable naturally occurring isotopes of rhodium and iridium. Complete Table 1.1.
Define relative isotopic mass.
Use Table 1.2 to calculate the relative atomic mass, $A_r$, of iridium in the alloy. Give your answer to two decimal places.
Hydrated rhodium(III) chloride, $\text{RhCl}_3\cdot x\text{H}_2\text{O}$, has $20.5\%$ by mass of water of crystallisation. Deduce the integer value of $x$ in $\text{RhCl}_3\cdot x\text{H}_2\text{O}$. Show your working.
Define stereoisomers.
Explain how the conversion of ethene to but-2-ene can be described as an addition reaction.
Draw the two stereoisomers of but-2-ene.