Which kind of nuclear decay does not alter the identity of the atom?

gamma decay

Explanation:

1. Alpha decay: In this process, alpha particles is emitted when a heavier nuclei decays into lighter nuclei. The alpha particle released has a charge of +2 units.

2. Beta-decay: In this process, a neutron gets converted into a proton and an electron releasing a beta-particle. The beta particle released carries a charge of -1 units.

3. Gamma decay: in this process, an unstable nuclei gives off excess energy by a spontaneous electromagnetic process and releases . These radiations does not carry any charge and are electrically neutral and thus the identity of the atom undergoing gamma decay do not change.