【单选题】已知 H 3 PO 4 的 pK a1 ,pK a2 ,pK a3 分别为 2.12,7.20,12.36,则 PO 4 3- 的 pK b1 为( )。
【单选题】测定熔点在80 °C以下固体药物熔点时,可选用下列哪种物质做传温液
【简答题】People may sing or dance with their friends there.
【单选题】He doesn't like _____, but he enjoys _____. [ ]
【单选题】— Can you sing a song in English? — No, I ________________. [ ]
【单选题】The girl _____________ very well. [ ]
【单选题】测定熔点在80°C以下固体药物熔点时,可选用下列哪种物质做传温液( A )
【单选题】测定熔点在80°C以下固体药物熔点时,可选用下列哪种物质做传温液()
【单选题】“Can you sing the song in English?” “No , I _________” [ ]