For each of 3 trials state the following:

heat needed to melt the ice (q)

Enthalpy of fusion

Percent error from the accepted enthalpy of fusion of water of 334 J/g

answers: to make sure that all of the broken pieces of tablet were added to the water, to allow for fair comparison of all three trials, with different particle sizes to avoid experimental error

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.