An excess of nico3, 12 g, was added to 40cm cube of sulpheric acid, 2.0 mol/dm cube. the unreacted nickel carbonate was filtered out and the filtrate evaporated to optain the crystals. calculate the number of moles of nico3 reacted, calculate the mass of nichel carbonate reacted, mass of un reacted nichel with the process

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.

catya your not at all which answer i've seen you do this on another question!