Final answer:
The product of the nuclear reaction where Aluminium-27 absorbs an alpha particle and emits a neutron is Phosphorus-30.
Step-by-step explanation:
When Aluminium-27 absorbs an alpha particle and emits a neutron, the resulting nuclear reaction can be understood through the conservation of atomic and mass numbers. Here, the atomic number increases by 2 and the mass number increases by 3, subtracting one for the lost neutron. Given that Aluminum's atomic number is 13, the product's atomic number will be 15, which corresponds to Phosphorus. Considering the mass number, starting from 27 and adding 4 (for the alpha particle) then subtracting one for the neutron yields a mass number of 30. Therefore, the product of this nuclear reaction is Phosphorus-30 (P-30).