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You are titrating 40 mL of a 0.25 M HF solution with a 0.20 M LiOH solution. What is the pH after adding 30 mL of the LiOH solution? The Ka of HF is 3.5 x 10-4.  Write the answer with the last digit in the tenths place like 7.2.  

What is the pH of a solution made by mixing 250 mL of 0.10 M HClO4 and 160 mL of a 0.15 M Ca(OH)2?  Write your answer with the last digit in the tenths place, like 13.1.

Estimate ΔG°rxn for the following reaction at 825 K.               2 Hg(g) + O2(g) →  2 HgO(s)            ΔH°=  -304.2 kJ;  ΔS°= -414.2  J/K   -2.63 kJ -37 kJ +37 kJ +645 kJ

Determine the equilibrium constant for the following reaction at 298 K.               SO3(g) + H2O(g) → H2SO4(l)         ΔG° = -90.5 kJ   1.37 × 10-16 4.78 × 1011 9.11 × 10-8 7.31 × 1015

You are titrating 40 mL of a 0.25 M HF solution with a 0.20 M LiOH solution. What is the pH after adding 60 mL of the LiOH solution? The Ka of HF is 3.5 x 10-4.  Write the answer with the last digit in the tenths place like 7.2. 

What is the pH of a 1L buffer consisting of 0.25 M HCHO2 and 0.30 M LiCHO2 after adding 0.15 moles of LiOH, assuming no change in volume. The pKa of HCHO2 is 3.74. 3.09 3.74 4.39 13.2

Which of the following solutions is a good buffer system? A solution that is 0.10 M HC2H3O2 and 0.10 M LiC2H3O2 A solution that is 0.10 M HBr and 0.10 M KC2H3O2 A solution that is 0.10 M HI and 0.10 M NH4+ A solution that is 0.10 M NaOH and 0.10 M KOH

Calculate ΔGrxn at 298 K under the conditions shown below for the following reaction.               3 O2(g)  → 2 O3(g)                     ΔG° = +326 kJ                         P(O2) = 0.41 atm, P(O3) = 5.2 atm   +341 kJ +17.8 kJ +332 kJ -47.4 kJ

If the equilibrium constant for the reaction shown below is 1.62 x 1016 at 298 K, what is the equilibrium constant at 655 K? HCN(g) + 2 H2(g) → CH3NH2(g)    ΔH° =  -158 kJ Write your answer with three significant figures.

Calculate ΔG°rxn using the following information.             NO(g) + O(g) →  NO2(g)                      ΔG°rxn = ?               2 O3(g) → 3 O2(g)                                ΔG°rxn = +489.6 kJ             O2(g) → 2 O(g)                                     ΔG°rxn = +463.4 kJ             NO(g) + O3(g) → NO2(g) + O2(g)       ΔG°rxn = – 199.5 kJ   +753.5 kJ +277.0 kJ -676.0 kJ -1152.5 kJ