Explain how a convection current forms when a pan of water is being heated over a stove

The covection current forms because the base of the pan heats up as it gains energy from the stove via conduction, the pan then subsequently heats the water that is close to the bottom. As the water gains heat the convection current forms as the hot air at the bottom of the pan rises since the heat gain has lowered the density of the water. As the hot water rises the cooler water sinks to the bottom and is then heated itself, this water will then rise and again it will be replaced by cooler water, therefore the convection current has been formed.