In modern Miller—Urey experiments it is assumed that carbon and nitrogen in the early atmosphere were present as
A) methane (CH4 ) and ammonia (NH3)
B) carbon dioxide (CO2 ) and nitrogen (N2)
C) carbonates (CO3-) and nitrates (NO3-)
D) carbon and nitrogen atoms
B
You might also like to view...
Which of the following statements about matter—antimatter engines is not true?
A) Matter—antimatter engines would be great in theory, but to date we have no evidence that antimatter even exists. B) Matter—antimatter reactions represent the most efficient possible reactions in terms of energy release. C) Spacecraft powered by matter—antimatter engines could probably reach speeds of more than half the speed of light. D) One of the major challenges to developing matter—antimatter engines is finding a way to store antimatter after it is produced.
Characteristic K x-rays are the result of:
a. inner electron transitions. b. outer electron transitions. c. nuclear electron states. d. buckytubes.
In a plane wave, the wavefronts are
a. circular b. flat c. parallel d. perpendicular to the direction of propagation
The fluids that are considered in this text:
(A) Have relatively low viscosities (B) Must be subjected to a normal stress to have motion (C) Have molecules that move relatively slowly (D) Move when subjected to any shear stress