Calculating with Q=P_cM

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Background

At a given temperature, the heat exchanged during a phase change is a function of a constant for that substance and the mass of the substance as expressed in the following equation

Heat = (Phase Change Constant)(Mass) or Q=P_cm
calories = (calories/gram)(grams)

Textbook Discussion: Sections 7.8, page 224. See Also: Example VI, page 225.

Problem

Calculate the number of kilocalories of heat exchanged during the evaporation (liquid --> gas) of 315 grams of a liquid substance at 10.0 degrees C. The absolute value of liquid/gas phase change constant for this substance at 10.0 degrees C is 421 cal/g. Express your answer so that it indicates both the quantity (kilocalories) and the direction (sign) of the heat flow for the substance during the phase change?