A﹣H是初中化学常见的物质,其相互转化关系如图所示,其中A是人体胃液中帮助消化的物质,B是用于改良酸性土壤的碱.
Hello,I'm Bill. I like swimming.This is my father.He likes reading.This is my mother.She likes singing.This is my brother.He likes skating.This is my sister.She likes dancing.What about you?
人体摄入锌不足会引起多种疾病,缺锌患者可在医生指导下通过服用葡萄糖酸锌口服液来补锌。已知葡萄糖酸锌的化学式为:C12H22OxZn,其相对分子质量为455,求:
“不敢高声语,恐惊天上人”.这里的“高”指的是声音的 ____(填“音调”“响度”或“音色”)大.月宫里的嫦娥不会听到你说话的声音,因为 ____不能传声.
北魏孝文帝将都城从平城迁到( )