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ziro4ka [17]
3 years ago
9

an atom has 79 protons, 78 electrons and a mass number of 118. how many neutrons does this atom have​

Chemistry
1 answer:
igomit [66]3 years ago
4 0

Answer:

39

Explanation:

Electrons weigh almost nothing, so their mass doesn't really matter for these types of problems. Just subtract 118-79 to find the remaining mass which is for the neutrons.

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3 0
3 years ago
Work=? time=5s Power = 40w
antiseptic1488 [7]

Answer:

200 J

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5 0
3 years ago
Will medal!!!
hjlf
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m = mass of substance (g)
C = Specific heat capacity (4.18)
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5 0
3 years ago
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Veronika [31]

Answer:

30 protons

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30 protons, 34 neutrons, and 30 electrons.

3 0
2 years ago
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