Determine the mass of CO2 produced by burning enough of each fuel to produce 1.00×102 kJ of heat. a. CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g) ΔH°rxn = –802.3 kJ
In a sunny location, sunlight has a power density of about 1 kW/m2. Photovoltaic solar cells can convert this power into electricity with 15% efficiency. If a typical home uses 385 kWh of electricity per month, how many square meters of solar cells are required to meet its energy requirements? Assume that electricity can be generated from the sunlight for 8 hours per day.
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Verified Solution
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Key Concepts
Power Density
Efficiency of Solar Cells
Energy Consumption and Conversion
Methanol (CH3OH) has been suggested as a fuel to replace gasoline. Find ΔH°rxn, and determine the mass of carbon dioxide emitted per kJ of heat produced. Use the information from the previous exercise to calculate the same quantity for octane, C8H18. How does methanol compare to octane with respect to global warming?
The kinetic energy of a rolling billiard ball is given by KE = 1/2 mv2. Suppose a 0.17-kg billiard ball is rolling down a pool table with an initial speed of 4.5 m/s. As it travels, it loses some of its energy as heat. The ball slows down to 3.8 m/s and then collides head-on with a second billiard ball of equal mass. The first billiard ball completely stops and the second one rolls away with a velocity of 3.8 m/s. Assume the first billiard ball is the system. Calculate q.