Answer:
1.) ⁴₂He
2.) ⁶₂He
3.) ²⁴²₉₄Pu
4.) ¹₀n
Explanation:
The superscript represents the mass number, which is the total amount of protons and neutrons in an element.
The subscript represents the atomic number, which is the total amount of protons in an element.
You can identify the element based on the atomic number. For instance, all atoms with a subscript/atomic number of 2 must always be helium (He). An element with an atomic number of 0 is represented by the symbol "n". The mass number and atomic numbers must be equal on both sides of the reaction.
1.) ¹₁H + ³₁H → ⁴₂He
-----> Mass Number: 1 + 3 = 4
-----> Atomic Number: 1 + 1 = 2
2.) ⁹₄Be + ¹₁H → He + ⁶₂He
-----> Standard helium (He) has a mass number of 4 and an atomic number of 2
-----> Mass Number: 9 + 1 - 4 = 6
-----> Atomic Number: 4 + 1 - 2 = 2
3.) ²³⁹₉₂U + ⁴₂He → ²⁴²₉₄Pu + ¹₀n
-----> Mass Number: 239 + 4 - 1 = 242
-----> Atomic Number: 92 + 2 - 0 = 94
4.) ²⁷₁₃Al + ¹₀n → ²⁴₁₁Na + ⁴₂He
-----> Mass Number: 24 + 4 - 27 = 1
-----> Atomic Number: 11 + 2 - 13 = 0