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nydimaria [60]
2 years ago
15

What were the four elements that ancient Greeks believed to exist

Chemistry
1 answer:
ruslelena [56]2 years ago
4 0

Answer:

The ancient Greeks believed in the four elements of air, earth, fire, and water. The Greek philosopher Empedocles is known for originating the theory of these classic four elements being the basis of all things.

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A large cyclotron directs a beam of He++ nuclei onto a target with a beam current of 0.250 mA. (a) How many He++ nuclei per seco
nikitadnepr [17]

Answer:

a. 7.8*10¹⁴ He⁺⁺ nuclei/s

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Explanation:

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(B).

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(C).

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Using Avogadro's ratio,

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Explanation:

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