下列关于氢氧化钙的叙述中，不正确的是（ ）
A．氢氧化钙溶液敞放在空气中会变质
B．氢氧化钙的溶解度随温度的升高而升高
C．氢氧化钙在农业上可改良酸性土壤
D．氢氧化钙的俗名叫做熟石灰、消石灰
A、氢氧化钙溶液可与空气中的二氧化碳反应生成碳酸钙，因此敞放在空气中的氢氧化钙溶液会变质成碳酸钙沉淀；
B、氢氧化钙微溶于水，且其溶解度随温度升高而减小；
C、氢氧化钙呈碱性且腐蚀性不强，可与酸性土壤中的酸发生中和反应而改良酸性土壤；
D、氢氧化钙在生活中被称为熟石灰，工业上又称其为消石灰；
故选B
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