Given that the bond energy of N2 is 946 kJ/mole, the bond energy of O2 is 498 kJ/mole and the NO bond energy is 631 kJ/mole, how much energy is required to react 1 mole of nitrogen molecules according to the following reaction?
N2 + O2 ? 2 NO
A) 182 kJ
B) -182 kJ
C) 813 kJ
D) -813 kJ
E) 2075 kJ
Answer: A
You might also like to view...
Why do astronomers need different telescope designs to observe across the electromagnetic spectrum?
A) New telescopes incorporate new technology to increase their efficiency. B) Telescopes have to adapt to the greater distortion of the atmosphere at shorter wavelengths. C) Photons of different energy have different wavelengths, some of which are not accessible from Earth's surface and require different collection strategies. D) Light pollution is worse at radio wavelengths than visible wavelengths. E) Astronomers and engineers enjoy the challenge of making new telescope designs.
A barge is 10 m wide and 60 m long and has vertical sides. The bottom of the boat is 1.2 m below the water surface. What is the weight of the barge and its cargo, if it is floating in fresh water of density 1000 kg/m3?
A) 3.5 MN B) 6.4 MN C) 6.8 MN D) 7.1 MN E) 9.5 MN
A fluid flows at 5 m/s over a wide, flat plate 15-cm-long. For each of the following list, calculate the Reynolds number at the downstream end of the plate. Indicate weather the flow at that point is laminar, transition, or turbulent. Assume all fluids are at 40°C.
(a) Air
(b) CO2
(c) Water
(d) Engine Oil
GIVEN
A fluid flows over a flat plate
Fluid velocity (U?) = 5 m/s
Length of plate (L) = 15 cm = 0.15 m
Fluid temperature = 40°C
FIND
The Reynolds number at the downstream end of the plate (ReL) for
(a) Air
(b) CO2
(c) Water
(d) Engine Oil
Indicate if the flow is laminar, transitional, or turbulent
ASSUMPTIONS
Steady state
SKETCH
PROPERTIES AND CONSTANTS
A sound wave radiates from a source in all directions. If the power of the sound source is 200 watts, then the intensity of the sound wave 100 m from the source is
A. 2.2 milliWatts/m2. B. 2.0 milliWatts/m2. C. 1.8 milliWatts/m2. D. 1.6 milliWatts/m2. E. 1.2 milliWatts/m2.