Answer
Balanced nuclear equation:
$^{190}_{78}Pt -- \gt ^{186}_{76}Os + ^4_2He$
Work Step by Step
1. Identify the reaction.
- In an $\alpha$ decay, the initial atom emits a particle with 2 neutrons and 2 protons $(_2^4He)$.
2. Determine the atomic number and symbol for : $platinum$, and write its complete symbol.
- 78 and "Pt". Therefore, the symbol for platinum-190 is: $^{190}_{78}Pt$.
3. Now, subtract 4 from the mass number, and 2 from the atomic number:
$^{190}_{78}Pt --\gt ^{186}_{76}?$
4. Identify the symbol for the element with atomic number equal to 76.
- It is "Os". So, the main product of that reaction will be: $^{186}_{76}Os$
5. Write the complete equation:
$^{190}_{78}Pt -- \gt ^{186}_{76}Os + ^4_2He$