Answer:
very unlikely to be found in dirt
Explanation:
That combination has a ratio of ¹⁴N to ¹⁵N of 10:4 = 2.5: 1. The most ¹⁵N enriched natural material has a ratio of ¹⁴N to ¹⁵N on the order of 250 : 1 or higher. The combination shown is very unlikely to be found in dirt.
Answer: A. An early form of chemistry that people used to try to turn metal
into gold.
Explanation:
Alchemy is indeed an early form of chemistry in which people try to turn metal into gold.
Answer: If a reaction releases 675,000 Joules then it means it releases 161.328872 kcal.
Explanation:
According to the standard conversion,
Therefore, 675,000 Joules will be converted into kcal as follows.
Thus, we can conclude that if a reaction releases 675,000 Joules then it means it releases 161.328872 kcal.
Answer:
In science, a model is a representation of an idea, an object or even a process or a system that is used to describe and explain phenomena that cannot be experienced directly. Models are central to what scientists do, both in their research as well as when communicating their explanations.
