No, the atomic number is not conserved in a radioactive decay. Radioactive decay is a process in which the nucleus of an unstable atom spontaneously transforms into a more stable configuration by emitting radiation. There are different types of radioactive decay, including alpha decay, beta decay, and gamma decay.
In alpha decay, an alpha particle (consisting of two protons and two neutrons) is emitted from the nucleus. This reduces the atomic number of the parent atom by 2 because it loses two protons.
In beta decay, a neutron in the nucleus is transformed into a proton, and an electron (beta particle) is emitted. The atomic number increases by 1 because a neutron is converted into a proton.
In gamma decay, no particles are emitted, but the nucleus releases energy in the form of gamma rays. Gamma decay does not change the atomic number or mass number of the nucleus.
Therefore, in general, the atomic number is not conserved during radioactive decay. It can either decrease (in alpha decay) or increase (in beta decay), depending on the specific type of decay.