皂化值是挥发油中的() ["A.酸值加皂化值","B.皂化值减酸值","C.酸值减皂化值","D.羧酸和酚类成分总和","E.酸值与酯值之和"]
慢性胃炎的膳食治疗原则是() ["多量多餐","多量少餐","少量少餐","少量多餐","少量饮酒"]
挥发油溶于乙醚,再用5%碳酸氢钠萃取,可得到() ["酸性成分","碱性成分","醇类成分","醛类成分","酮类成分"]
某气体反应在密闭容器中建立了化学平衡,如果温度不变但体积缩小了一半,则平衡常数为原来的多少?() ["3倍","1/2","2倍","不变"]
挥发油溶于乙醚,再用1%盐酸萃取,可得到() ["酸性成分","碱性成分","醇类成分","醛类成分","酮类成分"]
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