If the temperature of 24.6 g of calcium is decreased from 48.8 °C to 15.0 °C. How much heat has been released by calcium? Is the reaction exothermic or endothermic?
( the specific heat of calcium at 25 ^ C is 0.647)
A. q= 538 joules, the reaction is endothermic
B. q= 538 joules, the reaction is exothermic
C. q= -538 the reaction is endothermic
D. q= -538 joules, the reaction is exothermic

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