• 2022-06-05
    欲配制pH=3.5的缓冲溶液,应选择的缓冲对是()
    A: HCOOH(pKa=3.76)和HCOONa
    B: HPO(pKa1=2.16)和NaHPO
    C: NHCl和NH(pKb=4.75)
    D: HAc(pKa=4.75)和NaAc
  • A

    内容

    • 0

      欲配置pH=10的缓冲溶液,最好应选择的缓冲对是 A: HAc-NaAc[pKa(HAc)=4.75] B: NH3-NH4Cl[pKb(NH3)=4.75] C: HCOOH-HCOONa [pKa (HCOOH)=3.75] D: NaH2PO4-Na2HPO4 [pKa2(H3PO4)=7.2]

    • 1

      欲配置pH=5.0的缓冲溶液,应选择的最佳缓冲对是 ( ) A: HAc-NaAc [pKa(HAc)=4.75] B: NH3-NH4Cl [pKb(NH3)=4.75] C: HCOOH-HCOONa [pKa(HCOOH)=3.75] D: Na2HPO4-Na3PO4 [pKa3(H3PO4)=12.36]

    • 2

      欲配制pH=3的缓冲溶液,下列缓冲对比较合适的是( ) A: HCOOH—HCOONa (pKa=3.75) B: Ac-NaAc(pKa=4.75) C: NaHCO3一Na2CO3(pKa=10.25) D: HCN—NaCN (pKa=9.2)

    • 3

      配制pH=9.30的缓冲溶液,下列缓冲对中最合适的是() A: NaHCO-NaCO(HCO的pKa=10.33) B: HAc-NaAc(HAc的pKa=4.756) C: NHCl–NH·HO(NH·HO的pKb=4.75) D: NaHPO–NaHPO(NaHPO的pK=12.32) E: CHCOOH–CHCOONa(CHCOOH的pK=4.87)

    • 4

      欲配制pH=10的缓冲溶液,应选用( )缓冲对。‌ A: HCOOH-HCOONa [pKa⊙(HCOOH) = 3.75] B: HAc-NaAc [pKa⊙(HAc) = 4.74] C: NaH2PO4- Na2HPO4 [pKa2⊙(H3 PO4) = 7.21] D: NH3-NH4Cl [pKb⊙(NH3) = 4.75]