A butane burner is being used to heat water. The $M_r$ for butane is 58. The $\Delta H_c^\circ$ of butane is $-2877\,\text{kJ mol}^{-1}$. A mass of $250\,\text{g}$ of water is warmed from $12\,^{\circ}\text{C}$ up to $100\,^{\circ}\text{C}$. The burner passes $47\%$ of the heat released by the burning fuel to the water. Assume that the butane burns completely and that no water evaporates. What is the minimum mass of butane that has to be burnt?
- A0.068 g
- B1.85 g
- C3.94 g
- D4.48 g