The reaction scheme shows some reactions of calcium. [Figure 2.0]

1. (a)(i)Reaction 1 produces Ca(NO3)2 and one other product. Identify the other product.[1]
2. (a)(ii)Construct an equation for the thermal decomposition of Ca(NO3)2(s).[1]
3. (a)(iii)State the trend in the thermal stability of the Group 2 nitrates down the group.[1]
4. (a)(iv)In reaction 3, excess CO₂ is bubbled through water containing CaCO3. A solution of Ca(HCO3)2(aq) forms. Construct an equation for reaction 3.[1]
5. (b)Describe how Ca(OH)2 is used in agriculture.[1]
6. (c)(i)Describe how sp hybridised orbitals are formed.[1]
7. (c)(ii)Sketch a diagram to show how two sp hybrid orbitals can form a sigma (σ) bond.[2]
8. (d)(i)Reaction 5 can be used to prepare NH3. CaCN2 + 3H2O → CaCO3 + 2NH3 Calculate the minimum mass, in tonnes, of calcium cyanamide, CaCN2, that is required to produce 1.50 × 10⁶ tonnes of NH3. Show your working. 1 tonne = 1.00 × 10⁶g minimum mass of CaCN2 = ................................ tonnes[2]
9. (d)(ii)Draw the structure of the organic products formed in the following reactions. [Figure 2.1][3]

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