To become an operative part of the Constitution, an amendment, whether proposed by Congress or a national constitutional convention, must be ratified by either: 1  The legislatures of three-fourths (at present 38) of the states; or. 2  State ratifying conventions in three-fourths (at present 38) of the states.
But more of that in a second. The Earthâs atmosphere is composed of the following molecules: nitrogen (78%), oxygen (21%), argon (1%), and then trace amounts of carbon dioxide, neon, helium, methane, krypton, hydrogen, nitrous oxide, xenon, ozone, iodine, carbon monoxide, and ammonia.
37 Chapter 20: An Envelope of Gas: Earthâs Atmosphere and Climate 1. The very first Earth atmosphere, forming with Earth itself, was probably dominated by the cosmically abundant gases ________. A. nitrogen and oxygen B. hydrogen and helium C. carbon dioxide and methane D. water vapor and sulfur dioxide 2.