chapter 5 questions
A gummy bear contains 2.67g os sucrose (C12H22O11) when it reacts with 0.0587 mol KClO3, 43.7 KJ of Heat are produced. Determine ∆Hrxn for C₁₂H₂₂O₁₁+8KClO₃→12CO₂+11H₂)+8KCl
-5960kj/mol
how much heat is produced by the combustion of 126g of CH₄ in KJ (unit conversion factor -890.8 kj/mol)
-6941 KJ
A piece of unknown metal weighs 217 g. When the metal piece absorbs 1.43 kJ of heat, its temperature increases from 24.5 °C to 39.1 °C. Determine the specific heat of this metal.
0.45 J/g C
When 50.0 mL of 1.00 M HCl(aq) and 50.0 mL of 1.00 M NaOH(aq), both at 22.0 °C, are added to a coffee cup calorimeter, the temperature of the mixture reaches a maximum of 28.9 °C. What is the approximate amount of heat produced by this reaction in KJ? HCl(aq)+NaOH(aq)→NaCl(aq)+H₂O(l)
2.89 kJ
A 360-g piece of rebar (a steel rod used for reinforcing concrete) is dropped into 425 mL of water at 24.0 °C. The final temperature of the water was measured as 42.7 °C. Calculate the initial temperature of the piece of rebar. Assume the specific heat of steel is approximately the same as that for iron (Table 5.1), and that all heat transfer occurs between the rebar and the water (there is no heat exchange with the surroundings). c= 0.449
248 C
A 248-g piece of copper is dropped into 390 mL of water at 22.6 °C. The final temperature of the water was measured as 39.9 °C. Calculate the initial temperature of the piece of copper. Assume that all heat transfer occurs between the copper and the water. c= 0.385
38.7 C
A flask containing 8.0 102 g of water is heated, and the temperature of the water increases from 21 °C to 85 °C. How much heat did the water absorb in joules?
5.05e4 J
the galileo thermometer contains 125g of water. if the temperature increases from 18°C to 30°C, how much heat will the water absorb in joules?
6300J
When 3.12 g of glucose, C6H12O6, is burned in a bomb calorimeter, the temperature of the calorimeter increases from 23.8 °C to 35.6 °C. The calorimeter contains 775 g of water, and the bomb itself has a heat capacity of 893 J/°C. How much heat was produced by the combustion of the glucose sample?
This reaction released 48.7 kJ of heat when 3.12 g of glucose was burned.