Physical Chemistry Answers

The reaction of ammonia gas to nitrogen monoxide gas yields nitrogen gas and water vapor. How many moles of each reactant will be present if 13.8 moles of nitrogen gas is produced?

100 ml of raw water sample on titration ith N/50 H2SO4 required 12.4 ml of acid to phenolphthalein end point and 15.2 ml of the acid to methyl orange end point. Determine the types and extent of alkalinity.

In the reaction Mg(OH)2 + 2HCl → MgCl2 + 2H2 O, you were given 15 grams of Mg(OH)2 and 25 grams of HCl. Which of the two reactants is the limiting reagent? How much MgCl2 will be produced in the reaction? (Mg(OH)2 = 58.32 g/mol, HCl = 36.46 g/mol, MgCl2 = 95.32 g/mol)

50 ml of an alkaline water sample requires 3.7 ml of 0.02 N HCL upto phenolphthalein end point and 4.8 ml of complete Neutralization. Find the type and amount of alkalinity in water sample.

50 ml of an alkaline water sample requires 3.7 ml of 0.02 N HCL upto phenolphthalein end point and 4.5 ml of complete Neutralization. Find the type and amount of alkalinity in water sample.

50 ml of an alkaline water sample requires 3.7 ml of 0.02 N HCL upto phenolphthalein end point and 4.5 ml of complete Neutralization. Find the type and amount of alkalinity in water sample.

To get a sense of the effect of cellular conditions on the ability of adenosine triphosphate (ATP) to drive biochemical processes, compare the standard Gibbs energy of hydrolysis of ATP to ADP (adenosine diphosphate) with the reaction Gibbs energy in an environment at 37 °C in which pH = 7.0 and the ATP, ADP, and Pi− concentrations are all 1.0 mmol dm−3.

Consider the cell, Zn(s)|ZnCl2(0.0050 mol kg−1)|Hg2Cl2(s)|Hg(l), for which the cell reaction is Hg2Cl2(s) + Zn(s) → 2 Hg(l) + 2 Cl−(aq) + Zn2+(aq). The cell potential is +1.2272 V, E⦵(Zn2+,Zn) = −0.7628 V, and E⦵(Hg2Cl2,Hg) = +0.2676 V. (a) Write the Nernst equation for the cell. Determine (b) the standard cell potential, (c) ΔrG, ΔrG⦵, and K for the cell reaction, (d) the mean ionic activity and activity coefficient of ZnCl2 from the measured cell potential, and (e) the mean ionic activity coefficient of ZnCl2 from the Debye–Hückel limiting law. (f) Given that (∂Ecell/∂T)p = −4.52 × 10−4 V K−1, Calculate ΔrS and ΔrH.

For a hydrogen/oxygen fuel cell, with an overall four-electron cell reaction 2 H2(g) + O2(g) → 2 H2O(l), the standard cell potential is +1.2335 V at 293 K and +1.2251 V at 303 K. Calculate the standard reaction enthalpy and entropy within this temperature range.

One ecologically important equilibrium is that between carbonate and hydrogencarbonate (bicarbonate) ions in natural water. (a) The standard Gibbs energies of formation of CO32−(aq) and HCO3−(aq) are −527.81 kJ mol−1 and −586.77 kJ mol−1, respectively. What is the standard potential of the HCO3−/CO32−,H2 couple? (b) Calculate the standard potential of a cell in which the cell reaction is Na2CO3(aq) + H2O(l) → NaHCO3(aq) + NaOH(aq). (c)Write the Nernst equation for the cell, and (d) predict and calculate the change in cell potential when the pH is changed to 7.0 at 298 K.