I think the correct answer would be A. When a polonium atom with 84 protons, 124 neutrons, and 84 electrons undergoes alpha decay, a lead atom would be produced with 82 protons, 122 neutrons, and 84 electrons together with an alpha particle having two protons and two neutrons.
For this problem we can use half-life formula and radioactive decay formula.
Half-life formula,
t1/2 = ln 2 / λ
where, t1/2 is half-life and λ is radioactive decay constant.
t1/2 = 8.04 days
Hence,
8.04 days = ln 2 / λ
λ = ln 2 / 8.04 days
Radioactive decay law,
Nt = No e∧(-λt)
where, Nt is amount of compound at t time, No is amount of compound at t = 0 time, t is time taken to decay and λ is radioactive decay constant.
Nt = ?
No = 1.53 mg
λ = ln 2 / 8.04 days = 0.693 / 8.04 days
t = 13.0 days
By substituting,
Nt = 1.53 mg e∧((-0.693/8.04 days) x 13.0 days))
Nt = 0.4989 mg = 0.0.499 mg
Hence, mass of remaining sample after 13.0 days = 0.499 mg
The answer is "e"
The energy density is calculated by dividing the energy given by the mass of the material. From this item, the energy is 78 kcal and the mass is 50 grams. Performing the operation will give us an answer of 1.56 kcal/grams.
Answer:
Explanation:
Many elements have one or more isotopes that are radioactive these are called radioisotopes their their nuclei are unstable so they break now or decay and emit radiation
Answer:
D orbitals begin filling with electrons after the orbital found in the 4s sublevel is filled. This occurs because the d sublevel
Explanation:
hope this helps:D
(brainliest appriciated)
