Class+Notes

===__The Calorimetry Mini Problem Set__! Here, you will nominate a scribe from each group who will write a description of how to find the solutions to problems 1-7. The answer itself is already on the little sheet.===

Part b: Use the equation Q=m∙c∙∆T. The asnwer from part a is the heat transferred. Since the number of moles of NaCl is insignificant compare to water, use water's density to calculate the mass and use water's specific heat capacity. Substitute the values into the equation Q=m∙c∙∆T to solve for ∆T, then find Tf by adding ∆T to Ti. || △T and get Q=10460000J. Then, change the unit to KJ, so Q=10460 KJ. Given that, 1 mole of CH4 releases 900KJ, so the number of moles needed to heat water equal to 10460/900=11.62mol. Then 11.62 mol X 16g/mol = 185.92 g. ||
 * Question Number || Descriptive Answer ||
 * 1 ||  ||
 * 2 || Part a: Multiply the volume of the acid/base by it's concentration to find the number of moles of each reactant, and determine the limiting reactant. Then multiply the number of moles of the limiting reactant by the heat of neutraliztion of HCl with NaOH to get the answer.
 * 3 || First find Q using the formula Q=mc
 * 4 ||  ||
 * 5 || First calculate the number of moles of NH4NO3 and H2O and find the limiting reactant, then multiply the number of moles of the limiting reactant by the change in heat to find "Q", then use Q=mc(Tf-Ti) to find the change in temperature. [Note: since NH4NO3 is a solid and H2O is a liqud we use the mass of H2O instead of combinig the masses.] ||
 * 6 ||  ||
 * 7 || First, state all of your givens (volume of water, initial temperature, final temperature). Then calculate the change in temperature and calculate the mass of the man by converting the volume of the water (in litres) to grams. Next, use the formula Q=mc(Tf-Ti) to calculate the rate at which the man is giving off heat. Your answer will be in J and the last step is to convert that to kJ. For the second part of the question, you must multiply the answer you found in part a by 24 hours (because there are 24 hours in a day). This will give you the number of kJ he gives off in 1 day. ||



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