A 7.85 × 10^-5 mol sample of copper-61 emits 1.47 × 10¹⁹ positrons in 90.0 minutes. What is the decay constant for copper-61?

Question

Quizplus · Accepted Answer

The decay constant (λ) can be calculated using the formula λ = (ln(2) / t₁/₂), where t₁/₂ is the half-life. However, since the number of decays and the time are given, we can use the formula λ = (decays/time) / (initial number of atoms). The initial number of atoms is calculated from the moles of copper-61. After calculating, λ is approximately 0.207 h⁻¹.

A 785 × 10-5 Mol Sample of Copper-61 Emits 1

A 785 × 10^-5 Mol Sample of Copper-61 Emits 1