Question

The Standard Hydrogen Electrode (S.H.E.) consists of H2 gas bubbled through a solution of H+ ions; which of the following conditions must be met to give E0 = 0.00V, as part of the S.H.E.?

I. Temperature of cell is 298 K

II. Pressure of the Hydrogen gas is 1 atm

III. Concentration of H+ is 1.0 moldm-3 Select one:

a. I and II only

b. I and III only

c. I only

d. I, II and III

Use the data below which shows the standard electrode potentials of some half cells to answer the question that follows

Ag+(aq) + e- ⇌ Ag(s)	+0.80V
Cu2+(aq) + 2e- ⇌ Cu(s)	+0.34V
Zn2+(aq) + 2e- ⇌ Zn(s)	-0.76V
Na+(aq) + e- ⇌ Na(s)	-2.71V

Which two half cells would give the most powerful battery when connected?

Select one:

a. Na and Zn  

b. Ag and Na

c. Zn and Cu

d. Ag and Cu

The following equation has an equilibrium constant K_eq= 2 x10^-5. Which of the following correctly describes the standard electrode potential, E°, and the standard Gibbs free energy change, ∆G°?

Cu(s) + 2H⁺(aq) → Cu²⁺(aq) +H₂(g)

Select one:

a. Both ∆G° and E° are zero

b. ∆G° is negative and E° is positive

c. ∆G° is positive and E° is negative

d. Both ∆G° and E° have the same sign

Which of the following is NOT true for the boiling point of a liquid?

Select one:

a. The boiling point of the liquid can vary if it is not pure.

b. It is the temperature at which the vapour pressure equals external pressure

c. At sea level, it is the temperature when the vapour pressure reaches 760 mmHg.

d. It is the temperature at which particles can leave the liquid phase and enter the gas phase.

Answer 1