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Niobium-91 has a half of 680 years. After 2.040 years, how much niobium-91 will remain from a 750.00-g sample

User Cwtuan
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2 Answers

2 votes

Answer: C. 37.5 g

Explanation: On edge 2021

User Ben Rollert
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Niobium-91 will remain 93.75 g

Further explanation

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.

Usually radioactive elements have an unstable atomic nucleus.

The main particles are emitted by radioactive elements so that they generally decay are alpha (α), beta (β) and gamma (γ) particles

General formulas used in decay:


\large{\boxed{\bold{N_t=N_0((1)/(2))^{T/t(1)/(2) }}}

T = duration of decay

t 1/2 = half-life

N₀ = the number of initial radioactive atoms

Nt = the number of radioactive atoms left after decaying during T time

Half life -t1/2 of Niobium-91 =680 years

T=duration time=2040 years

No=initial sample=750 g

Niobium-91 will remain :


\tt Nt=750(1)/(2)^(2040/680)\\\\Nt=750.(1)/(2)^3\\\\Nt=93.75~g

User Jeffre
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