An element with mass number 81 contains 31.7% more neutrons as compared to protons. Assign the atomic symbol.

Asked by Abhisek | 1 year ago |  77

##### Solution :-

Let the No. protons in the element be x.

Therefore, No. neutrons in the element

= x + 31.7% of x

= x + 0.317 x

= 1.317 x

Given, Mass number of the element = 81,

which implies that (No. protons + No. neutrons) = 81

$$\Rightarrow x+1.317x=81\\ \\$$

$$2.317x=81\\ \\$$

$$x=\dfrac{81}{2.317}\\ \\$$

$$=34.95\\ \\$$

$$x\simeq 35$$

Therefore, total no. protons = 35, which implies that atomic number = 35.

Therefore, the element is $$_{35}^{81}\textrm{Br}$$

Answered by Pragya Singh | 1 year ago

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