The mineral substances known as are found in the blood and include sodium and potassium.

Substances known as electrolytes are found in blood which includes sodium and potassium.

Explanation:

Electrolytes are electrically charged particles and they help in moving nutrients into the cell and removing waste particles out of the cell. Other functions of electrolytes include maintaining the salt level as well as pH level of the body.  

The electrolyte potassium is present in small quantities in the fluid part of blood, namely plasma.

Regulating body muscle contraction is the main function of potassium. The fluid region outside cells contains a major portion of sodium which maintains the water balance of the body.

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.