An exothermic reaction releases 80.5 J of energy. How many calories of energy are released in the reaction?
In order to solve this we should know how many calories makes a joule.
1 calorie = 4.184 Joules
we can write two conversion factors using the above equation;
1 calorie / 4.184 Joules and 4.184 Joule/ 1 calorie
80.5 calorie x ( 4.184 Joule / 1 calorie)