要配置pH = 5.0 的缓冲溶液,下列哪个缓冲对适合( )
A: HAc-NaAc (pKaθ = 4.74)
B: NaH2PO4-Na2HPO4 (pKa2θ = 7.21)
C: NH3-NH4Cl (pKbθ = 4.74)
D: NaHCO3-Na2CO3 (pKa2θ = 10.33)
A: HAc-NaAc (pKaθ = 4.74)
B: NaH2PO4-Na2HPO4 (pKa2θ = 7.21)
C: NH3-NH4Cl (pKbθ = 4.74)
D: NaHCO3-Na2CO3 (pKa2θ = 10.33)
举一反三
- 欲配制pH=9.30的缓冲溶液,下列缓冲对中最合适的是( ) A: NaHCO3-Na2CO3(H2CO3的pKa2= 10.33) B: HAc-NaAc(HAc的pKa= 4.75) C: NH3-NH4Cl(NH3的pKb=4.75) D: NaH2PO4-Na2HPO4(H3PO4的pKa2= 7.21)
- 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]
- 要配制pH=4的缓冲溶液,应选用() A: NaH2PO4-Na2HPO4(pKa1=2.12,pKa2=7.20) B: HCOOH-HCOONa(pKa=3.74) C: HAc-NaAc(pKa=4.74) D: NaHCO3-Na2CO3(pKa1=6.38,pKa2=10.25)
- 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]