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The enthalpy of combustion of C15H32 is −10 040 kJ mol−1. (i) Calculate the maximum amount of energy that the complete combustion of 1.75 g of pentadecane can release. (ii) The energy from burning the 1.75 g sample is used to heat…
Pentadecane produced by cyanobacteria can be used as a biofuel. Explain why burning this biofuel adds less to the long-term buildup of atmospheric carbon dioxide than burning the same mass of pentadecane refined from crude oil.
Pentadecane can be cracked into smaller molecules. Consider the reaction: C15H32(g) → 3 C4H8(g) + C3H8(g) where C4H8 is but-1-ene. (i) Use the bond enthalpies in section 12 of the data booklet to determine ΔH⊖ for this reaction.…
But-1-ene is converted into butan-2-ol in a single reaction. State the corresponding equation.
Butan-2-ol reacts with octadecanoic (stearic) acid to form an ester that is used as a lubricant. C17H35COOH(l) + CH3CH(OH)CH2CH3(l) ⇌ C17H35COOCH(CH3)CH2CH3(l) + X(l) (i) Identify the by-product X(l) and state the type of reaction taking place. (ii)…
The equilibrium constant, Kc, for the reaction in (f) is 6.4 × 10−5 at 80 °C. (i) 1.00 dm3 of a mixture that is initially 0.20 mol dm−3 in octadecanoic acid and 0.20 mol dm−3 in butan-2-ol is…
Ammonium ions and phosphate ions combine to form an ionic compound. What is its formula? A. NH4PO4 B. (NH4)2PO4 C. (NH4)3PO4 D. NH4(PO4)3
(i) Iodine molecules, I2, undergo homolytic fission when they absorb light. Write an equation for this process, using curly arrows to show the movement of the electrons. (ii) In the presence of a suitable reagent the I–I bond can instead break…
The boiling points of the five simplest straight-chain primary amines, CH3NH2 to CH3(CH2)4NH2, and of the five simplest 1-fluoroalkanes, CH3F to CH3(CH2)4F, are plotted below against the number of carbon atoms in the molecule. An…
(i) Draw the structural formula of 2-chloropentane and that of the structural isomer in which the chlorine atom is attached to a tertiary carbon atom. (ii) Only one of the two isomers drawn in (c)(i) is chiral. Draw stereochemical formulas showing its two…