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Scrat [10]
3 years ago
7

Jeffrey is making a model of tungsten for his chemistry class. He has foam balls for the protons, neutrons, and electrons. He ha

s added 21 electrons to his model so far. How many more electrons does he need to add to complete his neutral atom of tungsten?
A. 1
B. 22
C. 31
D. 53
Chemistry
1 answer:
mrs_skeptik [129]3 years ago
8 0

Atomic number (Z) of tungsten is 74

Mass number (A) of tungsten is 184

Now:

Atomic number of an element = Number of protons = Number of electrons

Mass number = Number of Protons + Number of neutrons

In the case of tungsten

Total Number of electrons = 74

Jeffrey has already added 21 electrons

Number of electrons needed = 74 - 21 = 53

Ans (D) 53 more electrons are needed to complete the neutral atom of tungsten.

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