Question

What happens when magma is heated? Does it rise or does it sink, does it become more or less dense?

Answer 1

When magma is heated, it becomes less dense and rises. Magma, which is molten rock beneath the Earth's surface, is generated due to the heat and pressure in the mantle. As it is heated, the increased temperature causes the individual mineral grains within the magma to move more rapidly and spread out. This increased thermal energy decreases the density of the magma, making it less dense compared to the surrounding rock. Consequently, this less dense magma rises towards the surface through fractures and weak points in the Earth's crust, leading to volcanic activity.