When 100 grams of calcium carbonate are heated and then reweighed, the weight of the solid product is 56 grams. does this violate the law of conservation of mass? explain your answer.

When hydrochloric acid reacts with potassium hydroxide solution, the following reaction occurs. hcl (aq) + koh (aq) h2o (l) + kcl (aq) the reaction gives off heat energy, so it is an reaction.

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Describe at least two advantages and two disadvantages of using hydropower as a source of energy.