Answer and Explanation: Many nuclei are radioactive, which means they emit particles to become stable. In the process, they also become a different element. There are 3 types of decay:
Problem #1:
1.) Astatine: Z = 85 and A = 211
Alpha decay: [tex]{{A=211} \atop {Z=85}} \right. At[/tex] ⇒ [tex]{{207} \atop {83}} \right. Bi + {{4} \atop {2}} \right. \alpha[/tex]
The isotope created is Bismuth
Characteristics: Z = 83; e⁻ = 83; n = A - Z = 207 - 83 = 124
The isotope is Bismuth with 83 protons, 83 electrons and 124 neutrons.
Problem #2
1.) Lead: Z = 82 and A = 82
Beta decay: [tex]{{209} \atop {82}} \right. Pb[/tex] ⇒ [tex]{{209} \atop {81}} \right. Tl+{{0} \atop {-1}} \right. \beta[/tex]
The isotope created is talium.
2.) [tex]{{209} \atop {82}} \right. Pb[/tex] ⇒ [tex]{{209} \atop {81}} \right. Tl+{{0} \atop {-1}} \right. \beta[/tex]
[tex]{{209} \atop {81}} \right. Tl[/tex] ⇒ [tex]{{205} \atop {79}} \right. Au+{{4} \atop {2}} \right. \alpha[/tex]
[tex]{{205} \atop {79}} \right. Au[/tex] ⇒ [tex]{{205} \atop {78}} \right. Pt+{{0} \atop {-1}} \right. \beta[/tex]
3.) The isotope created is [tex]{{205} \atop {78}} \right. Pt[/tex].
p⁺ = 78; e⁻ = 78; n = 127
The isotope created ahs 78 protons, 78 electrons and 127 neutrons.