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Imagine that you dissolve 10.0 g of a mixture of NaNO3 and KF in 100.0 g of water and find that the temperature rises by 2.22 °C. Using the following data, calculate the mass of each compound in the original mixture. Assume that the specific heat of the solution is 4.18 J/(g · °C).
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General Chemistry
- A 50-mL solution of a dilute AgNO3 solution is added to 100 mL of a base solution in a coffee-cup calorimeter. As Ag2O(s) precipitates, the temperature of the solution increases from 23.78 C to 25.19 C. Assuming that the mixture has the same specific heat as water and a mass of 150 g, calculate the heat q. Is the precipitation reaction exothermic or endothermic?arrow_forwardAlloys When a 58.8-g piece of hot alloy is placed in125 g of cold water in a calorimeter, the temperature ofthe alloy decreases by 106.1°C, while the temperature ofthe water increases by 10.5°C. What is the specific heat ofthe alloy?arrow_forwardA 0.470-g sample of magnesium reacts with 200 g dilute HCl in a coffee-cup calorimeter to form MgCl2(aq) and H2(g). The temperature increases by 10.9 C as the magnesium reacts. Assume that the mixture has the same specific heat as water and a mass of 200 g. (a) Calculate the enthalpy change for the reaction. Is the process exothermic or endothermic? (b) Write the chemical equation and evaluate H.arrow_forward
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- In a coffee-cup calorimeter, 150.0 mL of 0.50 M HCI is added to 50.0 mL of 1.00 M NaOH to make 200.0 g solution at an initial temperature of 48.2C. If the enthalpy of neutralization for the reaction between a strong acid and a strong base is 56 kJ/mol, calculate the final temperature of the calorimeter contents. Assume the specific heat capacity of the solution is 4.184 J/g C and assume no heat Joss to the surroundings.arrow_forwardWhat mass of acetylene, C2H2(g), must be burned to produce 3420 kJ of heat, given that its enthalpy of combustion is 1301 kJ/mol? Compare this with the answer to Exercise 5.91 and determine which substance produces more heat per gram.arrow_forwardIn a calorimetric experiment, 6.48 g of lithium hydroxide, LiOH, was dissolved in water. The temperature of the calorimeter rose from 25.00C to 36.66C. What is H for the solution process? LiOH(s)Li(aq)+OH(aq) The heat capacity of the calorimeter and its contents is 547 J/C.arrow_forward
- The temperature of the cooling water as it leaves the hot engine of an automobile is 240 F. After it passes through the radiator it has a temperature of 175 F. Calculate the amount of heat transferred from the engine to the surroundings by one gallon of water with a specific heat of 4.184 J/g oC.arrow_forwardThe process of dissolving ammonium nitrate, NH4NO3, in water is an endothermic process. What is the sign of q? If you were to add some ammonium nitrate to water in a flask, would you expect the flask to feel warm or cool?arrow_forward9.41 Under what conditions does the enthalpy change equal the heat of a process?arrow_forward
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