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【题目】下列物质溶于水时,溶液温度明显降低的是(

A.氯化钠

B.硝酸铵

C.浓硫酸

D.氢氧化钠

【答案】B

【解析】A项,氯化钠溶于水时吸收的热量和放出的热量相当,溶液温度基本保持不变.B项,硝酸铵溶于水时吸收的热量多,溶液温度明显降低.C项,浓硫酸稀释时放出的热量多,溶液温度明显升高.D项,氢氧化钠溶于水时放出的热量多,溶液温度明显升高.

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