Which statement is true if the Delta. Hrxn of a reaction is positive? The reaction is endothermic. The reaction is exothermic. There is more reactant than product. There is more product than reactant.

The reaction is endothermic.

Explanation:

Heat is absorbed in endothermic reactions. An endothermic process is any process which requires or absorbs energy from its surroundings, usually in the form of heat. It may be a chemical process, such as dissolving ammonium nitrate in water, or a physical process, such as the melting of ice cubes (wikipedia)

Standard Enthalpy of Reaction (ΔHrxn) is the amount of heat absorbed (+ΔH value) or released (-ΔH value) that results from a chemical reaction.