Draw the form of a p orbital.
Write an equation that represents the first ionisation energy of silicon.
Explain why the first ionisation energies of the elements generally rise across Period 3.
Element A is in the p block. The graph gives the successive ionisation energies for removing the first ten electrons of A. State and explain the group of the Periodic Table to which element A belongs.
The table gives data for $^{28}_{14}\text{Si}$, $^{29}_{14}\text{Si}$ and $^{30}_{14}\text{Si}$. A silicon sample contains $92.2\%$ $^{28}_{14}\text{Si}$. The combined percentage abundance of $^{29}_{14}\text{Si}$ and $^{30}_{14}\text{Si}$ in the sample is $7.8\%$. The relative atomic mass, $A_r$, of silicon in the sample is $28.09$. Calculate the percentage abundance of $^{30}_{14}\text{Si}$. Give your answer to one decimal place.
Silicon reacts with nitrogen gas to produce $\text{Si}_3\text{N}_4$. $\text{Si}_3\text{N}_4$ is a solid with a melting point of $1900^\circ\text{C}$. It does not dissolve in water and does not conduct electricity when molten. Suggest the type of bonding in and structure of $\text{Si}_3\text{N}_4$. Explain your answer.
Sulfur-containing compounds, such as $\text{C}_2\text{H}_5\text{SH}$, are found in fossil fuels and produce $\text{SO}_2$ when burned. Write the equation for the complete combustion of $\text{C}_2\text{H}_5\text{SH}$.
State why the presence of $\text{SO}_2$ in the atmosphere has environmental consequences. Describe one consequence for the environment.
In one reaction, $\text{SO}_2$ reacts with $\text{O}_3$ until dynamic equilibrium is reached. $\text{SO}_2(g) + \text{O}_3(g) \rightleftharpoons \text{SO}_3(g) + \text{O}_2(g)$. State and explain how an increase in pressure affects the composition of the equilibrium mixture.
In the other reaction, a different equilibrium is established at $300\,\text{K}$ as shown. $3\text{SO}_2(g) + \text{O}_3(g) \rightleftharpoons 3\text{SO}_3(g) \quad \Delta H = +462.3\,\text{kJ mol}^{-1}$. Suggest a temperature needed to increase the yield of $\text{SO}_3$ at equilibrium. Explain your answer.