Identify the materials labeled in the image. Label the molten material found at point A.
magma

Label the molten material found at point B.

it would be a gas formation

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante