UNICAMP 2020: Nuclear fusion is a reaction in which atomic nuclei merge to form the nucleus of a new atom

UNICAMP 2020: Nuclear fusion is a reaction in which atomic nuclei merge to form the nucleus of a new atom. The mass of the new atom’s nucleu...

UNICAMP 2020: Nuclear fusion is a reaction in which atomic nuclei merge to form the nucleus of a new atom. The mass of the new atom’s nucleus is lower than the sum of the merging nuclei’s masses, a difference that is released as energy. This is, for instance, the reaction that occurs in the Sun.

The energy released during fusion can be calculated by the equation E = Δmc², where Δm is the difference between the initial and final masses in the reaction, and c is the speed of light.

When calculating the aforementioned energy, nucleus mass can be conveniently quantified using the atomic mass unit (u), which is roughly equivalent to 900 MeV (1 u → 900 MeV). Consider the hypothetical nuclear fusion reaction ²²²X + ⁴Y → ²²¹Z. Note that the masses of ²²²X, ⁴Y, and ²²¹Z are 222 u, 4 u, and 221 u, respectively. The amount of energy released in this reaction is

a) 5 MeV.
b) 450 MeV.
c) 900 MeV.
d) 4500 MeV.

QUESTÃO ANTERIOR:
- UNICAMP 2020: A peça publicitária

RESOLUÇÃO:
A equação dada no texto

²²²X + ⁴Y → ²²¹Z

A diferença de massa entre o início e o fim da reação é de Δm = 5u

De acordo com o texto, temos:
1u _______ 900 MeV

Assim, a energia liberada é:

E = 5 . 900MeV
E = 4500MeV

GABARITO:
d) 4500 MeV.

PRÓXIMA QUESTÃO:
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QUESTÃO DISPONÍVEL EM:
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