Radioactivity-are unstable structures that decay to form other nuclides by emitting particles and electromagnetic radiation.
Three Features of Radioactivity
The earlier experiments, among them Rutherford and his co-workers, distinguished three components in the radiations from radio nuclides. These components were called Alpha, Beta, and Gamma.
ACTIVITIES AND HALF-LIFE
Activity
It is the rate at which the nuclei of its constituent atoms decay. If N is the number of nuclei present in the sample at a certain time, its activity R is given by
R= -dN/dt
The minus sign is used to make R a positive since dN/dt is, of course, intrinsically negative. The SI unit of activity is named after Becquerel:
1 becquerel = 1Bq = 1 decay/s
1 curie = 1 Ci = 3.70 x 1010 decays/s = 37 Gbq
Activity Law:
R=Roe–λt
λ – decay constant
Half-life
T1/2 = ln 2/λ = 0.693/λ
Radioactive Decay
N = Noe–λt
N – number of undecayed nuclei
t- time
λ – decay constant
No– number of undecayed nuclei at t=0
Mean Lifetime
T = T1/2/0.693 = 1.33T1/2
Radioactive Series
– A series consisting of a succession of daughter products all ultimately derived from a single parent nuclide.
Alpha Decay
Disintegration Energy:
Q = (mi – mf – mx)c2
Alpha Particle Energy:
KEα≈A-4/A
Beta Decay
n p + e– + v
Gamma Decay
A nucleus can exist in states whose energies are higher than that of its ground state, just as an atom can. An excited nucleus is denoted by an asterisk after its usual symbol, for instance Sr*. Excited nuclei return to their ground states by emitting photons whose energies correspond to the energy differences between the various initial and final states in the transitions involved. The photons emitted by nuclei range in energy up to several MeV, and are traditionally called gamma rays.
What is the Main Cause of a Heart Attack? What is its Solution? A heart attack is the blockage of… Read More
In the vast economic arena, one term that often takes center stage, inciting extensive debates and discussions, is the "debt… Read More
De-Dollarization: The Changing Face of Global Finance The financial landscape is in a state of flux, with an intriguing economic… Read More
The curtains closed on a dramatic Bundesliga season with Bayern Munich standing tall once again, clinching their 11th straight title.… Read More
The Unfolding Story of Celine Dion's Health In recent news that has left fans across the globe stunned, iconic singer… Read More
As the echoes of the recent NBA season start to fade, the attention of enthusiasts is firmly glued to one… Read More