10.18 - Key 18 Consider the following equation CH4 2O2 CO2...

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Key: 18. Consider the following equation: CH 4 + 2O 2 → CO 2 + 2H 2 O Δ H (delta H)= -900 kJ/mol. You combust 24 g of methane and use the heat given off to warm up a sample of water. If the water is raised in temperature 50 ˚C, how much water is contained in the sample? a. 1.4 x 10 -2 kg b. 14 kg c. 6.5 kg d. 680 g e. 6.8 g e. None of the above This problem is a good example of the importance of paying attention to units. Whenever you see a problem where energy is used to heat up water, it is probably a specific heat problem. The specific heat of water is 4.186J/g˚C. Keeping that in mind, you should be able to use change in temperature(ΔT), energy input (J) and specific heat to solve for mass. Since we
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This document was uploaded on 11/04/2011 for the course CHEM 106 at BYU.

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