Hot spots are the areas on earth, located in the mantle, where the rocks melt to produce magma. The liberation of hot magma from the earth crust results in the volcanic eruption. Hawaiian islands, located in Pacific plate are example of hot spot volcanoes. This hot spot was active for 70 million years, resulted in the formation of volcanic chain that extended 3750 miles to the northwest region of the Pacific Ocean.
1 Some kind of light is emitted for each element when it is moved from higher energy level to lower energy level 2 Also some of energy is absorbed which is being used to move electrons from high energy level to lower energy level
A pure substance is a substance composed of one substance. It has fixed physical and chemical properties. It has special chemical symbols, which can be expressed by a chemical formula. Water is pure, so what you mean by liquid ice is pure.