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How many joules of heat are lost by 3580 kg of granite as it cools from 41.2°C to -12.9°C? The specific heat of granite is 0.803 J/(g·°C).

Swimming Pool A swimming pool measuring 20.0 m × 12.5 m is filled with water to a depth of 3.75 m. If the initial temperature is 18.4°C, how much heat must be added to the water to raise its temperature to 29.0°C? Assume that the density of water is 1.000 g/mL.

Food Preparation When 10.2 g of canola oil at 25.0°C is placed in a wok, 3.34 kJ of heat is required to heat it to a temperature of 196.4°C. What is the specific heat of the canola oil?

Alloys When a 58.8-g piece of hot alloy is placed in 125 g of cold water in a calorimeter, the temperature of the alloy decreases by 106.1°C, while the temperature of the water increases by 10.5°C. What is the specific heat of the alloy?

Write the sign of \(\Delta H_{ \text { sytem for each of the following }}\) changes in physical state. a. \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}(\mathrm{s}) \rightarrow \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}(1)\) b. \(\mathrm{H}_{2} \mathrm{O}(\mathrm{g}) \rightarrow \mathrm{H}_{2} \mathrm{O}(1)\) \(\mathrm{c} . \mathrm{CH}_{3} \mathrm{OH}(1) \rightarrow \mathrm{CH}_{3} \mathrm{OH}(\mathrm{g})\) \(\mathrm{d} . \mathrm{NH}_{3}(1) \rightarrow \mathrm{NH}_{3}(\mathrm{s})\)

The molar enthalpy of fusion of methanol is 3.22 \({kJ} / {mol}\) . What does this mean?

Explain how perspiration can help cool your body.

Grilling What mass of propane \(\left(\mathrm{C}_{3} \mathrm{H}_{8}\right)\) must be burned in a barbecue grill to release 4560 \(\mathrm{kJ}\) of heat? The \(\Delta H_{\mathrm{comb}}\) of propane is \(-2219 \mathrm{k} / \mathrm{mol} .\)

For a given compound, what does the standard enthalpy of formation describe?

How does ?H for a thermochemical equation change when the amounts of all substances are tripled and the equation is reversed?