(a) define the terms: - bond energy as the energy required to break one mole of a particular covalent bond in the gaseous state - bond length as the internuclear distance of two covalently bonded atoms (b) use bond energy values and the concept of bond length to compare the reactivity of covalent molecules

describe the following reactions of alkenes: (a) the electrophilic addition of (i) hydrogen in a hydrogenation reaction, \( H_2(g) \) and Pt/Ni catalyst and heat (ii) steam, \( H_2O(g) \) and \( H_3PO_4 \) catalyst (iii) a hydrogen halide, \( HX(g) \), at room temperature (iv) a halogen, \( X_2 \) (b) the oxidation by cold dilute acidified \( KMnO_4 \) to form the diol (c) the oxidation by hot concentrated acidified \( KMnO_4 \) leading to the rupture of the carbon–carbon double bond and the identities of the subsequent products to determine the position of alkene linkages in larger molecules (d) addition polymerisation exemplified by the reactions of ethene and propene