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3 years ago

How many protons are in an element with an atomic number of 8 and a mass number of 18?

Chemistry

2 answers:

klasskru [66]3 years ago

8 0

Answer : The number of protons in an element are 8.

Explanation :

Atomic number is defined as the number of protons or number of electrons.

Atomic number = number of protons = number of electrons

Mass number is defined as the sum of number of protons and number of neutrons.

Number of neutrons = Mass number - Number of protons

As we are given :

Atomic number of an element = 8

Mass number of an element = 18

Now we have to determine the number of protons for this element.

As, Atomic number = number of protons = number of electrons

So,

Atomic number = Number of protons = 8

Hence, the number of protons in an element are 8.

Natalija [7]3 years ago

4 0

The answer is 8. atomic number: the number of protons in the nucleus of an atom.

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