Ethyl chloride (C2H5Cl), a substance used as a topical anesthetic, is prepared by reaction of ethylene with hydrogen chloride: C2H4(g) + HCl(g) → C2H5Cl(g) ΔH° = -72.3 kJ. What is the value of ΔE (in kilojoules) for the reaction, assuming no work is done other than pressure-volume work?

Calculate the total amount of heat needed, in joules, to convert 75.0 grams of ice at -20°C to steam at 100°C. Given: the heat of fusion of water is 6.01 kJ/mol, the heat of vaporization is 40.7 kJ/mol, and the specific heats are: ice = 2.09 J/g°C, water = 4.18 J/g°C, steam = 2.00 J/g°C.

Determine the amount of heat (in kJ) required to vaporize 25 mL of mercury at its boiling point. For mercury, ΔHvap = 56.9 kJ/mol (at 357 °C). The density of mercury is 13.6 g/mL.

Determine whether the process of dry ice evaporating is endothermic or exothermic and indicate the sign of ΔH.

Which of the following processes for ethanol (C2H5OH) is endothermic?

Given 307.5 g of hot tea at 73.5 °C, what mass of ice at 0 °C must be added to obtain iced tea at 12.5 °C? The specific heat of the tea is 4.18 J/(g·°C), and ΔHfusion for ice is +6.01 kJ/mol.

Given 313.5 g of hot tea at 72.5 °C, what mass of ice at 0 °C must be added to obtain iced tea at 12.5 °C? The specific heat of the tea is 4.18 J/(g·°C), and ΔHfusion for ice is +6.01 kJ/mol.

Given 382.0 g of hot tea at 82.0 °C, what mass of ice at 0 °C must be added to obtain iced tea at 15.0 °C? The specific heat of the tea is 4.18 J/(g·°C), and ΔHfusion for ice is +6.01 kJ/mol.

Given 393.0 g of hot tea at 81.0 °C, what mass of ice at 0 °C must be added to obtain iced tea at 12.5 °C? The specific heat of the tea is 4.18 J/(g·°C), and ΔHfusion for ice is +6.01 kJ/mol.