已知某温度下，0.1 mo l · L-1的NaHB溶液中c(H＋)>c(OH－)，则下列关系式一定正确的是（ ）
A c(Na＋)=c(HB－)＋2c(B2－)＋c(OH－)
B c(Na＋) ="0.1" mo l · L-1≥c(B2－)
C c(H＋)c(OH－) =1x×10-14
D 溶液的PH=1
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