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]
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]
举一反三
- 欲配制pH=5的缓冲溶液,应选用下列( )共轭酸碱 对。 A: NH2OH2+—NH2OH(NH2OH的pKb=3.38) B: HAc-Ac-(HAc的pKa=4.74) C: NH +—NH •H O 4 3 2(NH3•H2O的pKb=4.74) D: HCOOH—HCOO-(HCOOH的pKa=3.74)
- 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]
- 欲配制pH=5.0缓冲溶液,应选用的缓冲对是 A: HCOOH-HCOONa pKaθ(HCOOH)=3.74 B: HAc-NaAc pKaθ(HAc)=4.74 C: H3BO3-NaH2BO3 pKaθ(H3BO3)=9.24 D: NH3-NH4Cl pKbθ(NH3)=4.74
- 5. 欲配制pH=5.0缓冲溶液,应选用的缓冲对是 A: HCOOH-HCOONa [pKa(HCOOH)=3.74] B: HAc-NaAc [pKa(HAc)=4.74] C: H3BO3-NaH2BO3 [pKa(H3BO3)=9.24] D: NH3-NH4Cl[pKb(NH3)=4.74]
- 欲配制pH=5.0的缓冲溶液,应选用( ) 缓冲对。 A: HCOOH-HCOONa [pKay (HCOOH) = 3.75] B: NH3-NH4Cl [pKby (NH3) = 4.75] C: NaH2PO4- Na2HPO4 [pKa2y (H3PO4) = 7.21] D: HAc-NaAc [pKay (HAc) = 4.74]