Aluminum has a specific heat of 0.900 J/gºC. How much energy in kJ is
needed to raise T of 635 g block from 30.7°C to 82.1°C? *
A)29.4 kJ
B)29,400 kJ
C)571.5 kJ
D).0000275 kJ

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.