A mixture of gaseous reactants is put into a cylinder, where a chemical reaction turns them into gaseous products. The cylinder has a piston that moves in or out, as necessary, to keep a constant pressure on the mixture of 1 atm. The cylinder is also submerged in a large insulated water bath. (See sketch at right.) 1 atm pressure piston cylinder From previous experiments, this chemical reaction is known to absorb 386. kJ of energy water bath gases The temperature of the water bath is monitored, and it is determined from this data that 181. kJ of heat flows out of the system during the reaction exothermic Is the reaction exothermic or endothermic? endothermic Does the temperature of the water bath go up or down? down neither in out neither does work work is done on it neither Does the piston move in or out? Does the gas mixture do work, or is work done on it? How much work is done on (or by) the gas mixture? Round your answer to 3 significant digits. kJ

A 155.0 g piece of copper at 181 oC is dropped into 250.0 g of water at 17.9 oC. (The specific heat of copper is 0.385 J/goC.) Calculate the final temperature of the mixture. (Assume no heat loss to the surroundings.)

thermometer. A sample of aluminum, which has a specific heat capacity of 0.897 J'g.°C', is put into a calorimeter (see sketch at right) that contains 100.0 g of water. The aluminum sample starts off at 92.4 °C and the temperature of the water starts off at 15.0 °C. When the temperature of the water stops changing it's 23.2 °C. The pressure remains constant at 1 atm. insulated container water sample Calculate the mass of the aluminum sample. Be sure your answer is rounded to 2 significant digits. a calorimeter Submit Assignment Continue 62021 McGraw Hill LLC. Al Rights Reserved. Terms of UseI Privacy Center Accessibility

Consider the following chemical reaction which produces nitric oxide from its constituent elements: N2 (g) + O2 (g) → 2 NO (g) ArH= 182.6 kJ/mol If nitrogen and oxygen were mixed and allowed to react under constant pressure conditions, which of the following statements must be true? Select as many answers as applicable however points will be deducted for incorrect guesses. The temperature of the surroundings would increase This is an endothermic reaction ΔΗ = ΔU The temperature of the surroundings would decrease ΔΗ = q