A:Ca(H2PO4)2
B:NH4H2PO4
C:CO(NH2)2
D:KCl
下列除去杂质(在括号内)选用的试剂(在箭头右侧)错误的是( )
-What colour are they?-They're ____.
判断对错.
含盐5%的盐水200克中,含水190克.
下列合并同类项结果正确的是( )
— Yes, I ____(take) it after breakfast.