242/96 Qr aftergoing through beta minus decay
Beta minus decay involves the emission of an electron or a positron from the nucleus. This changes the atomic number of the nucleus, but not its mass number.
In the case of 242/96 Qr, this means that a neutron within the nucleus is converted into a proton while emitting an electron. This results in the atomic number of Qr increasing from 96 to 97 but the mass number remaining the same at 242.
The resulting nucleus after beta minus decay would be 242/97 Bk (Berkelium).