Write alpha decay of americium-241 and name the daughter.

Solution & explanation

1. In alpha decay, the emitted helium nucleus has mass number 4 and atomic number 2.

2. Conserve nucleon number: subtract 4 from 241.

   $$A_d=241-4=237$$

3. Conserve charge: subtract 2 from 95.

   $$Z_d=95-2=93$$

4. Atomic number 93 identifies neptunium. The daughter is neptunium-237.

5. Write the balanced nuclear equation: ²⁴¹₉₅Am → ²³⁷₉₃Np + ⁴₂He. Verify 241 = 237 + 4 and 95 = 93 + 2.

²⁴¹₉₅Am → ²³⁷₉₃Np + ⁴₂He. Subtract 4 from mass number and 2 from atomic number; the daughter is neptunium-237.