Answer:
Second Earth's Atmosphere
The second atmosphere, which was the first to remain with the earth, was created by volcanic outgassing and comet ice. There was a lot of water vapor, carbon dioxide, phosphorus, and methane in this atmosphere, but absolutely no oxygen.
Explanation:
<em>It is a lava type.....</em>
The answer is D.
The atomic number stands for the number of protons in each element. The number of protons is what is unique to each element. The number of neutrons varies; this is what isotopes are. The number of protons being the atomic number explains why the atomic number is an identifying characteristic of each element.
Answer:
Table salt is considered to be a compound because it is made up of two elements (sodium and chloride,) while sodium itself is a raw element. That's why table salt is considered to be a compound, while sodium is not.
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