This is the area that we consider to form the outer shell of the Sun. Atoms with electrons are able to absorb and emit radiation, making this region more opaque, like a thick fog. In the convective zone , the energy is transferred much faster than it is in the radiative zone . This is because it is transferred through the process of convection.
Hotter gas coming from the radiative zone expands and rises through the convective zone.
It can do this because the convective zone is cooler than the radiative zone and therefore less dense. As the gas rises, it cools and begins to sink again. As it falls down to the top of the radiative zone, it heats up and starts to rise. This process repeats, creating convection currents and the visual effect of boiling on the Sun's surface. This is called granulation, as seen in the picture below.