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
举一反三
- 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: H3PO4(pKa1=2.16)和NaH2PO4 C: NH4Cl和NH3(pKb=4.75) D: HAc(pKa=4.75)和NaAc
- 今要配制pH=3.5的缓冲溶液,选用下面什么缓冲对最为合适? A: H3PO4—NaH2PO4(pKa1=2.13) B: HCOOH—HCOONa(pKa=3.76) C: H2C8H4O4—KHC8H4O4(pKa1=2.95) D: HAc—NaAc(pKa=4.75)
- 配制pH=9.0的缓冲溶液,应选用哪对缓冲对 A: NH4Cl—NH3·H2O (pKb=4.75) B: HCOOH—HCOONa (pKa=3.5) C: H2PO4-—HPO42-(pKa =7.21) D: HAc—Ac- (pKa =4.75)
- 配制pH=9.0的缓冲溶液,应选用哪对缓冲对 A: HCOOH—HCOONa (pKa=3.5) B: HAc—Ac- (pKa =4.75) C: NH4Cl—NH3·H2O (pKb=4.75) D: H2PO4-—HPO42-(pKa =7.21)
- 配制pH=9.0的缓冲溶液,应选用( )缓冲对。 A: H2PO4--HPO42-(pKa=7.21) B: NH4Cl-NH3·H2O (pKb=4.75) C: HCOOH-HCOONa (pKa=3.5) D: HAc-Ac-(pKa=4.75)
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]