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Andrew [12]
3 years ago
11

If an atom of an element has a mass number of 45 and it has 20 neutrons in its nucleus, what is the atomic number of the

Chemistry
1 answer:
HACTEHA [7]3 years ago
3 0

Answer:

Explanation:

uestion

If an atom of an element has a mass number of 45 and it has 20 neutrons in its nucleus, what is the atomic number of the

element?

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The transition from lower energy level to higher energy level require a gain of energy.

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Which of these measurements is expressed as three significant figures?
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Which of these measurements is expressed as three significant figures?  


C. 4.20 g


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When humans burn fossil fuels, most of the carbon quickly enters the_______
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Atmosphere.

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8 0
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How many meters did a car travel if it went 65mi/hr for 4.5 hours?
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