Convection, and radiation with a small amount of conduction cooks the marshmallow. The primary heat transfer is convection from the hot gasses passing over the marshmallow.
When a marshmallow is cooked over a fire, it uses the heat transfer method of conduction. The heat from the fire is directly transferred to the marshmallow through direct contact, causing it to melt and cook.
Well if you are roasting a marshmellow over a fire it will melt. But if you microwave it it will explode.
When roasting a marshmallow over a fire, chemical energy stored in the marshmallow is converted to thermal energy as the marshmallow heats up and starts to melt and brown. This is an example of energy transformation from chemical energy to thermal energy.
Roasting marshmallows over a campfire is an example of radiant heat. The heat is transferred from the fire to the marshmallow through electromagnetic waves.
To correctly roast a marshmallow, take the marshmallow and leave it on the left side of the fire until that side is perfectly roasted (by letting it heat and change color twice), then quickly move your mouse to the middle under the campfire doing the same thing and finally move your mouse to the right of the campfire and completely roast the marshmallow. Put the marshmallow on the empty plate and start again!
...chesnuts roasting on an open fire....
It depends on how long you roast it! If you simply allow it to warm up, it is still a marshmallow after roasting, so it is a physical change. If you like it crispy and burnt, it is a chemical change because it starts off white and then it eventually melts and turns brown. This browning is oxidation, a chemical process where some of the marshmallow's sugar is burnt and carbon dioxide is released into the air.
Chipmunks Roasting On an Open Fire was created in 2000.
Roasting over a free fire (the fire spits out burnt little pieces of wood)
THE CHRISTMAS SONG (Chestnuts Roasting on an Open Fire)
Chestnuts were roasting over an open fire.
Simpsons Roasting on an Open Fire was created on 1989-12-17.