Is coffee a mixture or compound

If anyone would be able to me out with these three questions it would be these are from the chem 2202 course.

Predict the reactants of this chemical reaction. that is, fill in the left side of the chemical equation. be sure the equation you submit is balanced. (you can edit both sides of the equation to balance it, if you need to.) note: you are writing the molecular, and not the net ionic equation. > cacl2(aq) + h20(l)

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.