Exothermic and endothermic reactions — practice question

One unlabelled bottle contains solid sodium carbonate, $\text{Na}_2\text{CO}_3$. A different unlabelled bottle contains solid sodium hydrogencarbonate, $\text{NaHCO}_3$. The reaction of sodium carbonate with dilute hydrochloric acid is exothermic. The reaction of sodium hydrogencarbonate with dilute hydrochloric acid is endothermic. Plan experiments based on the reaction of each solid with dilute hydrochloric acid: • to work out which solid is which • to decide which reaction gives the greater energy change per gram of solid. You may use any apparatus normally available in a chemistry laboratory, but no other chemicals. You should include every measurement you would take. Chemical equations are not needed.