Question

In: Chemistry

Calculate equilibrium concentrations for [H], [H2 PO4-,], [H3PO4] ;, [HPO4-2]; [PO4-3] if at the beginning the...

Calculate equilibrium concentrations for [H], [H2 PO4-,], [H3PO4] ;, [HPO4-2]; [PO4-3] if at the beginning the concentration of [H3PO4 is 0.100 M if K1=7.5 x 10^-3 for the first dissociation, and K 2= 6.2 x 10 ^-8, K3= 4.8 x10^-8

Expert Solution

-----H3Po4(aq) ------------> H^+ (aq) + H2PO4^- (aq)

I---- 0.1 --------------------- 0 ---------------- 0

C--- -x --------------------- +x --------------- +x

E ---- 0.1-x --------------- +x ----------------- +x

ka1 = [H^+][H2PO4^-]/[H3Po4]

7.5*10^-3 = x*x/(0.1-x)

7.5*10^-3 *(0.1-x) = x^2

x = 0.024M

[H^+] = x = 0.024M

[H2PO4^-] = x = 0.024M

[H3PO4] = 0.1-x = 0.1-0.024 = 0.076M

H2PO4^- (aq) -----------> H^+ (aq) + HPO4^2- (aq)

Ka2 = [H^+][HPO4^2-]/[H2Po4^-]

6.2*10^-8 = 0.024*[HPO4^2-]/0.024

[HPO4^2-] = 6.2*10^-8M

HPO4^2- (aq)--------------> H^+ (aq) + PO4^3- (aq)

Ka3 = [H^+][PO4^3-]/[HPO4^2-]

4.8*10^-8 = 0.024[PO4^3-]/6.2*10^-8

[PO4^3-] = 4.8*10^-8*6.2*10^-8/0.024 = 1.24*10^-13M

[H^+] = 0.024M

[H2PO4^-] = 0.024M

[H3PO4] = 0.076M

[HPO4^2-] = 6.2*10^-8M

[PO4^3-] = 1.24*10^-13M

queen_honey_blossom answered 2 years ago

For a 0.110 M H3PO4 solution, find the equilibrium concentrations of H3PO4, H2PO4-, HPO4^2-, PO4^3-, and...

For a 0.110 M H3PO4 solution, find the equilibrium concentrations of H3PO4, H2PO4-, HPO4^2-, PO4^3-, and H3O+. For H3PO4: Ka1= 7.5x10^-3, Ka2= 6.2x10^-8, Ka3= 4.2x10^-13

Calculate the pH of a 5.0 M H3PO4 solution and the equilibrium concentrations of the species...

Calculate the pH of a 5.0 M H3PO4 solution and the equilibrium concentrations of the species H3PO4, H2PO4-, HPO42- and PO43- (ka1 = 7.5 x 10-3, ka2 = 6.2 x 10-8, ka3 = 4.8 x 10-13)

What is the equilibrium concentration of PO4 in a 0.511 M solution of H3PO4 (Ka1 =...

What is the equilibrium concentration of PO4 in a 0.511 M solution of H3PO4 (Ka1 = 7.5E-3, ka2= 6.2E-8, ka3= 4.8E-13) I troes using the 5% rule but when i checked my work i was at 11%. I dont know how to solve this if i cant use the 5% rule. Help please.

Calculate the concentrations of H2C2O4, HC2O4^ -, C2O4^ -2, and H^+ species in a 0.430 M...

Calculate the concentrations of H2C2O4, HC2O4^ -, C2O4^ -2, and H^+ species in a 0.430 M Oxalic Acid Solution (Ka1 = 6.5 x 10^-2) (Ka2 = 6.1 x 10^-5) Be sure to answer in correct number of significant figures. H2C2O4 = ________ M HC2O4^- = _________ M C2O4^2- = _________ x 10 ^ (scientific notation) H^+ = ____________ M

Phosphoric acid, H3PO4(aq), is a triprotic acid. Calculate the pH and concentrations of H3O + (aq),...

Phosphoric acid, H3PO4(aq), is a triprotic acid. Calculate the pH and concentrations of H3O + (aq), H3PO4(aq), H2PO4 − (aq), HPO4 2− (aq), PO4 3− (aq), and OH− (aq) in a 0.100-M phosphoric acid solution at 25°C.

Calculate the pH and the concentrations of all species present in 0.18 M H 2 SO...

Calculate the pH and the concentrations of all species present in 0.18 M H 2 SO 3 . ( K a1 = 1.5× 10 −2 , K a2 = 6.3× 10 −8 ) Express your answer to three significant figures and include the appropriate units

Using the initial concentrations of [Fe(H2O)6]^3+, SCN^-, and the equilibrium concentration of the [Fe(H2O)5SCN]^2+ complex, calculate...

Using the initial concentrations of [Fe(H2O)6]^3+, SCN^-, and the equilibrium concentration of the [Fe(H2O)5SCN]^2+ complex, calculate the equilibrium concentrations of both [Fe(H2O)6]^3+ and SCN^-. All mol/L. Ice table is needed. Initial concentrations of [Fe(H2O)6^3+: Initial concentrations of SCN: [Fe(H2O)5SCN]^2+ equilibrium: Fe(H2O)6 - SCN - EQ Fe(H2O)5SCN 0.390 1.54 23.42 0.390 3.12 35.99 0.390 4.84 58.09 0.390 6.25 74.81 0.390 7.96 98.97

For the following reaction: H2(g) + I2(g)<--->2HI(g) ; Kc=49.5 The beginning concentrations are: H2: 0.10M, I2:...

For the following reaction: H2(g) + I2(g)<--->2HI(g) ; Kc=49.5 The beginning concentrations are: H2: 0.10M, I2: 0.050M, and HI:0 Assume this reaction is not at equilibrium. When it does reach equilibrium, what will the concentrations be?

Calculate the equilibrium concentrations of NH3, Cu2+, [Cu(NH3)]2+, [Cu(NH3)2]2+, [Cu(NH3)3]2+, and [Cu(NH3)4]2+ in a solution made...

Calculate the equilibrium concentrations of NH3, Cu2+, [Cu(NH3)]2+, [Cu(NH3)2]2+, [Cu(NH3)3]2+, and [Cu(NH3)4]2+ in a solution made by mixing 500.0 mL of 3.00 M NH3 with 500.0 mL of 2.00 x 10-3 M Cu(NO3)2. The sequential equilibria are Cu2+ (aq) + NH3(aq) ⇐⇒ [Cu(NH3)]2+ (aq) K1 = 1.86 x 104 [Cu(NH3)]2+ (aq) + NH3(aq) ⇐⇒ [Cu(NH3)2]2+ (aq) K2 = 3.88 x 103 [Cu(NH3)2]2+ (aq) + NH3(aq) ⇐⇒ [Cu(NH3)3]2+ (aq) K3 = 1.00 x 103 [Cu(NH3)3]2+ (aq) + NH3(aq) ⇐⇒ [Cu(NH3)4]2+ (aq)...

. The equilibrium constant for the reaction below is 7.796 x 10-9. Calculate the equilibrium concentrations...

. The equilibrium constant for the reaction below is 7.796 x 10-9. Calculate the equilibrium concentrations of all species if the initial Co3+ concentration is 0.425 M and the initial SO42- concentration is 0.113 M. 2 Co3+(aq) + 2 SO42-(aq)→← 2 Co2+(aq) + S2O82-(aq)