CHEM 110L - Experiment 5 Don't Get Stressed

I need help calculating the following.

Fill in this table based on given concentrations Ecell Hypothetical [Zn +2] [Cu *2] e transferred # 1 0.1 M 0.1 M 0.1 M # 2 1 x 10 -3 M # 3 0.1 M 1 x 10 -6 M # 4 0.1 M 1 x 10 -9 M

Determine the initial concentrations of Fe3+ and SCN- in each test tube. Solution  0.002M iron(III) nitrate in 1M nitric acid(mL) 0.002M potassium thiocyanate(mL) DI water(mL) Absorbance(A) 1 3 2 1 0.128 2 2 3 1 0.269

Calculate the [FeSCN2+] using volumes of stock solutions. Presume that all the SCN– ions react. STANDARD SAMPLE Volume of Fe(NO3)3 (mL) Volume of SCN- (mL) Volume of H2O (mL) [FeSCN2+] Absorbance 1 2.5 2.0 20.5   0.1918 2 2.5 1.5 21.0   0.3239 3 2.5 1.0 21.5   0.4965 4 2.5 0.5 22.0   0.6209 Stock [Fe(NO3)3] = 0.200 M, Stock [SCN-] = 0.0020 M   Any help would be greatly appreciated Please and thanks :)

I help calculating the following values please.

15

Pls help ASAP

Cu(s) + 2Ag*(aq) 2Ag(s) + Cu2+(aq) For the above reaction would the Ecell increase, decrease, or remain the same if the concentration of Ag* is halved and the [Cu2+] is reduced to 1/4 of the initial concentration. increase remain the same decrease can't tell

You will have to determine the equilibrium constant for the reaction between aqueous iron(III) ion and thiocyanate ion. The equilibrium equation is given below: Fe3+ (aq) + NCS– (aq) <---> FeNCS2+ (aq) yellow          colorless             red The absorbance of light is measured using a spectrophotometer. The higher the absorbance, the higher the concentration of FeNCS2+ present. At room temperature, 5.00ml of 0.200M iron(III)nitrate solution was mixed with 5.00ml of 0.200M potassium thiocyante solution. The absorbance of this mixture was 0.55. A 1cm thick cuvette was used. What are the equilibrium concentrations of Fe3+ and SCN- in our solution?

A student set up the reaction with 0.048 M Fe3+ and 1.0x10-4 M SCN. They end up with an equilibrium concentration of [Fe(SCN)]2+ of 4.7x10-5 M. Based on these results, what is the value of the equilibrium constant Ke?

For each of the following reactions, indicate if there is something wrong with the reaction. If something is wrong, say what it is. a) 2H2I + Oz+2H,Om b) Ca + HzO + CO + Ha Na + Hal + NH3 CE,O70 + H2O → 2HBrOejaql FeSO) + 2N2CE →Na,SO + FeCt AlCaa + H2Ou → Al(OH); + CH4) Pb(NO3)2ag) + K,COsjag) PbCOslas) + 2KNO3lag) HBrag) + Ba(OH)a 2H;O + BaBragl CaFa + HaSOejag 2Hfg + CasOe c) d) e) f) h) i) 2PbS + O2+ 2P6O + 2S02

-6 -5 -4 -3 -2 -1 +1 +2 +3 +4 +5 PbsO.(s) + H*(aq) + 2CI (aq) = Pb(s) + HSO. (aq) + Cl2(g)

Based on the provided chart of reduction potentials, rank the following chemicals from strongest (1) to weakest (5) oxidizing agents. Ered (V) +2.87 +1.33 +1.23 +1.06 +0.96 +6.77 +0.68 40.59 1054 ✓ +0.440 +0.34 0'defined -0.28 -0.83 1.66 -2.71 Half-Reaction Ashtimi ¹₂(g) +2€¯¯¯ 2F (aq) MnO4 (aq) + 8 H(aq) + Se Cl₂(g) +2e™ 2 Cl¯ (aq) Cr₂O₂(aq) + 14 H*(aq) + 6 e˜ — 2 Cr³" (aq) + 7 H₂O(1) O₂(g) + 4 H*(aq) + 4e¯¯ — 2H₂O(1) Br₂() +2 e 2 Br (ag) NO₂(aq) + 4 H* (aq) + 3 e¯ — NO(x) + 2 H₂0(1) Ag (aq) + e 20 ME Fe³+(aq) + e¯ —— Fe²¹ (aq) O(g)+2H^(aj) 24 HO(m) MnO, (aq) + 2H₂O(l) + 3e¯ —— MnO₂(s) + 4 OH¯(aq) L₂(s) + 2 ¤¯ ————— 21 (aq) O₂(g) + 2 H₂O(l) + 4 e Cu²+ (aq) + 2 e 2e 2H(aq) + 2 e Ni²" (aq) + 2e – Feª™ (aq) + 2 e Zn²+ (aq) + 2 2e — 2 H₂O(l) +2e Al (aq) + 3 e Na (aq) e Li(aq) + e H Mn² (aq) + 4H₂O(1) Cu(s) H₂(g) Ni(s) > Fe(s) Zn(s) Hag) + 2OH(aq) Al(s) —— Na(s) 40H (aq)

Chloride ions are added to the AglAg* half-cell of the cell Ag|Ag*l|Cu²*|Cu to precipitate AgCI (s). The cell voltage is then measured to be +0.072 V at 298 K. If [Cu2+] = 1.0 M in the Cu2+|Cu half cell, what is [Ag*] in the Ag|Ag* half-cell? (First step: You will need to use the data in Table 17-1 to calculate E°cell.) Give your answer to two significant figures. Ecell = E°cell - (0.0257 V/n) In(Q) E'cell = E°ox + E°red

1-For the reaction,  4 Cl- + Co(H2O)62+ <-->  CoCl42- + 6 H2O                     (color 1)                      (color 2) What color does the mixture of the two cobalt complexes form when placed in heat?   Group of answer choices   blue   pink   purple   No answer text provided.     2-For the reaction,  4 Cl- + Co(H2O)62+ <-->  CoCl42- + 6 H2O                     (color 1)                      (color 2)       2-Is heat a reactant or a product?   Group of answer choices   reactant   product   No answer text provided.   No answer text provided.

What would happen to the Fe2+ concentration if a reduced sample was exposed to lab air for too long

Which one of the following is the correct expression for the equilibrium constant for the reaction shown below? Ca2+(aq) + 2F–(aq)  ⇌  CaF2(s)   A.  K =  [Ca2+][F–]2   B.  K = [CaF2]  /  [Ca2+][F–]2   C.  K =  1 /  [Ca2+][F–]2   D.  K = 1 /  [Ca2+](2[F–])2   E.  None of the expressions

How many moles of Fe(OH)2 [Ksp = 1.8 × 10–15] will dissolve in 1 L of water buffered at pH = 12.00?   A)  1.8 × 10–11 mol   B)  1.8 × 10–9 mol   C)  5.0 × 10–12 mol   D)  8.0 × 10–6 mol   E)  4.0 × 10–8 mol

A student set up the reaction with 0.096 M Fe3+ and 1.0x10-4 M SCN". They end up with an equilibrium concentration of [Fe(SCN)]2+ of 8.3x10-5 M. Based on these results, what is the value of the equilibrium constant K?

4. ferric phosphate(s) + hydrochloric acid (ag) products -> 5. strontium carbonate(s) + sodium acetate (ag) products 6. aluminum oxide(s) + chloric acid (ag) products

For the following acid/base reactions, draw the products and indicate the equilibrium position.

Choose the correct equation for the reaction of HBr with Ca(OH)2.     Choices: 2H3O+ + 2Br– + Ca2+ + 2OH– → 4H2O + CaBr2 HBr + Ca(OH)2 → CaH + Br(OH)2 HBr + Ca(OH)2  H2O + CaBr 2H3O+ + 2Br– + Ca2+ + 2OH– → 4H2O + 2Br– + Ca2+

29. Fe,03 + CO - Fe+CO2 1,3, 2, 3 What coefficients are required to balance the equation above? 1,1, 2, 1 2, 6, 3, 6 1, 1, 2, 2 CLEAR ALL Unanswered ( PREVIOUS 23 24 25 26 O31 27 28 29 30

QUESTION 37 Based on the provided chart of reduction potentials, rank the following chemicals from strongest (1) to weakest (5) oxidizing agents. Half-Reaction End (V) +2.87 +1.51 +1.36 +1.33 +1.23 +1.06 +0.96 +0.80 +0.77 +0.68 +0.59 +0.54 +0.40 +0.34 0 [defined] -0.28 -0.44 -0.76 -0.83 -1.66 -2.71 -3.05 F2(8)+2e-2F (aq) MnO4 (aq) +8H(aq) +5e Mn²(aq) + 4H₂O(1) Cl₂(8)+2e-2 Cl(aq) Cr₂O72 (aq) +14 H(aq) + 6e2 Cr³(aq) + 7 H₂O(1) O₂(g) +4 H(aq) +4e-2H₂O(l) Brz(1)+2e-2 Br (aq) NO3(aq) + 4H(aq) + 3e NO(g) + 2H₂O(1) Ag (aq)+eAg(s) Fe³+ (aq) + e Fe²(aq) O₂(g) +2H(aq) +2e H₂O₂(aq) MnO4 (aq) + 2 H₂O(!)+3e MnO₂(s) + 4 OH(aq) 12(3)+2e-21 (aq) O₂(8)+2H₂O(1)+4e-4 OH(aq) Cu²(aq) +2e 2 H(aq)+2e Ni2(aq) +2e Fe (aq) +2e Cu(s) H-(8) Ni(s) Fe(s) Zn2(aq) +2e →→→ Zn(s) 2H₂O(1)+2e H₂(g) + 2OH(aq) Al(s) Al³(aq) + 3 e Na (aq)+eNa(s) Li' (aq) +eLi(s)

The concentration of glucose in an aqueous  solution can be determined by oxidation with ferricyanide ion, Fe(CN)63–.  The absorbance of the ferricyanide ion measured at 420 nm increases as the concentration of glucose increases. [Glucose], mg / mL Absorbance 0.005 0.132 0.010 0.290 0.020 0.498 0.030 0.642 0.040 0.750 Using the method of least-squares, give the equation of the best straight line through the points. Make sure that m=slope has 3 decimal places (XX.XXX) and y-intercept (b) has 2 significant figures (0.0XX). In your answer you should write in the form of y=mx+b. For instance, y = 12.316x + 0.072