What does it mean when someone has done multiple trials? A. They have performed an experiment once and reported their findings. B. They have performed a scientific experiment more than once. C. They have performed an experiment that can only be performed once. D. They have designed an investigation to answer a question.

A. They have performed an experiment once and reported their findings.

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.