How many moles of calcium chloride are there when you have 55.5 grams of calcium chloride(CaCl2)

Consider the following reactions. (note: (s) = solid, (l) = liquid, and (g) = gas.) mg(s) + ½o2(g) → mgo(s) + 146 kcal/mole h2(g) + ½o2(g) → h2o(g), δh = -57.82 kcal/mole what type of reaction is represented by the previous two examples?

Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.

Which of the following is most likely true about water in chemical solutions?