If a reaction releases more energy when new bonds are made than the amount of energy absorbed to break bonds in the reactants, which statement is true?

Which of these is an endothermic reaction?

On a reaction profile, what does the height of the hump represent?

If the energy change on an energy level diagram is negative, what does this tell you about the reaction?

Which of the following statements correctly explains why a reaction is endothermic?

Magnesium needs to be heated before it reacts with oxygen in the air. What conclusion can you draw from this?