Chemistry SL Paper 2, November 2025, TZ1

(i) The boxes for the 1s and 2s orbitals of a sulfur atom are shown below. Draw the remaining orbitals needed for its ground-state electron configuration, filling and labelling each one. Use section 7 of the data booklet. (ii) For a sulfur atom, sketch the…

4.81 g of sulfur was heated in a stream of chlorine gas until the reaction was complete. The mass of the chloride produced was 10.13 g. (i) Calculate how many atoms are present in this 4.81 g sample of sulfur. Use sections 2 and 7 of the data booklet. (ii)…

Another hydride of sulfur is hydrogen sulfide, $\ce{H2S}$; it forms a sulfonium ion, $\ce{H3S+}$. State the types of bonds present in the sulfonium ion, $\ce{H3S+}$, and explain how these bonds are formed.

Sulfur forms a dichloride, $\ce{SCl2}$. Deduce the Lewis formula of $\ce{SCl2}$.

Methanoic acid, $\ce{HCOOH(aq)}$, and hydrochloric acid, $\ce{HCl(aq)}$, are both acids. A $0.100\ \mathrm{mol\,dm^{-3}}$ solution of $\ce{HCOOH(aq)}$ has a pH of 2.39 while a solution of $\ce{HCl(aq)}$ of the same concentration has a pH of 1.00. (i) Explain…

(i) Oil of vitriol, spirit of hartshorn and wood alcohol are old trivial names still occasionally used for chemical substances, and names like these can be a source of confusion in international scientific communication. Outline how the modern system of naming…

(i) Calculate the enthalpy change, $\Delta H$, for the overall synthesis of propyl ethanoate from propane and ethane shown above. Use section 12 of the data booklet. (ii) Two students each calculated the enthalpy change for the reaction between propan-1-ol and…

For the overall reaction shown above, calculate the atom economy of this route from propane and ethane to propyl ethanoate. Use sections 1 and 7 of the data booklet.

(i) Deduce the expression for the equilibrium constant, $K$, for this reaction. (ii) $0.500\ \mathrm{mol}$ each of propan-1-ol and ethanoic acid, together with a small amount of concentrated sulfuric acid, reacted at constant volume. At equilibrium,…

(i) Sketch the Maxwell–Boltzmann energy distribution curve for the particles in this reaction mixture. Label the activation energy with and without the catalyst on the diagram. (ii) On the same axes, sketch and label a second Maxwell–Boltzmann curve for this…