A:当a=b时,c(H+)=c(OH﹣)+c(NH3•H2O)
B:当a>b时,c(NH4+)+c(NH3•H2O)>c(Cl﹣)
C:当a<b时,c(NH4+)>c(Cl﹣)>c(OH﹣)>c(H+)
D:当a与b为任意比时,c(NH4+)+c(H+)=c(Cl﹣)+c(OH﹣)
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Hello,everyone!____ name is Li Hua.I am 13 years old.I've got six____ at school.And my favourite is maths.I have three____ in the morning and two in the afternoon.I am____ but I am very happy____ I can learn a lot.
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在一朵花中,____和____是花的主要部分,花受精后,花的____将发育成果实,____ 成种子.
如图所示的LC振荡电路中,某时刻线圈中磁场方向向上,且电路的电流正在减小,则此时( )