A hot sample of unknown material is placed into a calorimeter containing 42.1 g of water at 22.0 °C. The final temperature of the water is 62.7 °C. The specific heat capacity of water is 4.184 J/g °C. What is the heat change for the water? Enter either a+ or - sign AND the magnitude. q,H,O (J) Enter

A hot sample of unknown material is placed into a calorimeter containing 42.1 g of water at 22.0 °C. The final temperature of the water is 62.7 °C. The specific heat capacity of water is 4.184 J/g °C. What is the heat change for the water? Enter either a+ or - sign AND the magnitude. q,H,O (J) Enter

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter7: Chemical Energy

Section: Chapter Questions

Problem 109AE: A sample of nickel is heated to 99.8C and placed in a coffee-cup calorimeter containing 150.0 g...

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A 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.
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