A typical bathtub can hold 100. gallons of water.

(a) Calculate the mass of natural gas that would need to be burned to heat the water for a tub of this size from 65 °F to 108 °F. Assume that the natural gas is pure methane, CH₄.

(b) What volume of natural gas does this correspond to at 25 °C and 1.00 atm? See Table 4D.1.

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TABLE 4D.1 Standard Enthalpies of Combustion at 25 °C* Substance benzene carbon ethanol ethyne (acetylene) glucose hydrogen methane. octane propane urea Formula C6H6(1) C(s, graphite) C₂H5OH(1) C₂H₂(g) С6H12O6(s) H₂(g) CH₂(g) C8H18 (1) C3H8(g) CO(NH2)2(s) ΔΗ/ (kJ.mol-¹) -3268 - 394 - 1368 - 1300. - 2808 - 286 - 890. -5471 - 2220. -632 Specific enthalpy/ Enthalpy density*/ (kJ.g-¹) 41.8 32.8 29.7 49.9 15.59 142 55 48 50.35 10.52 (kJ.L-¹) 3.7 X 104 7.4 X 104 2.3 × 104 53 2.4 X 104 12 36 3.4 x 104 91 1.4 X 104