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What is the cell potential at 25oC for the concentration cell described by: Cu(s) | Cu2+(aq, 0.15 M) || Cu2+(aq, 0.75 M) | Cu(s)

The pH of a 1.75 M solution of weak acid HA is 3.25. Calculate the value of Ka for HA.

For a certain reaction at 330 K, ∆Hsys = 9.9 kJ and ∆Ssys = 85 J/K, calculate ∆Suniv.

Calculate ΔG°rxn for the following reaction at 525 K. CH2O(g) +  2H2(g) → CH4(g)   +  H2O(g) ΔH° = -94.9 kJ;  ΔS° = -224.2 J/K Answer: ΔG°rxn  = [a] kJ

Determine the standard entropy change (∆So) for this reaction. 2HgO(s) ⟶2Hg(l) + O2(g) Substance (state) So (J/mol.K) HgO(s) 70.3 Hg(l) 75.9 O2(g) 205.2  

Use the following values to calculate ∆S for the sublimation of 1 mole of I2. I2(s) ⟶I2(g) Substance (state) So (J/mol.K) I2(s) 116.1 I2(g) 260.7

A certain reaction has an activation energy of 25.0 kJ/mol. At what temperature will the reaction proceed four times faster than it did at 375 K?

The pH of a 0.150 M solution of weak acid HA is 4.35. Calculate the value of Ka for HA.

Calculate the mass of copper metal that will be deposited by passing a 25.0 A current through a solution of copper(II) sulfate for 3.00 h. Cu2+(aq) + 2 e⁻  →  Cu(s)   You must show all of your work including units for credit.

Calculate ΔSsurr at 298 K. 2NO2(g) → N2(g) + 2O2(g) ΔH = -66.4 kJ