1.What fraction of the volume of each corner atom is actually within the volume

Question

1.What fraction of the volume of each corner atom is actually within the volume of a face-centred cubic unit cell?

Select one:

A. 1/16

B. 1/2

C. 1/4

D. 1/8

E. 1

2.

On a phase diagram, the critical temperature is ______.

Select one:

A. the temperature above which a gas cannot be liquefied

B. the temperature at which all three states are in equilibrium

C. the temperature required to cause sublimation of a solid

D. the temperature required to melt a solid

E. the temperature below which a gas cannot be liquefied

3.

Consider an electrochemical cell based on the reaction:

2 H+(aq) + Sn(s) Sn2+(aq) + H2(g)

Which of the following actions would not change the measured cell potential?

Select one:

A. addition of more tin metal to the anode compartment

B. increasing the tin(II) ion concentration in the anode compartment

C. increasing the pressure of hydrogen gas in the cathode compartment

D. lowering the pH in the cathode compartment

E. Any of the above will change the measured cell potential.

Explanation / Answer

Answer –

1)For the FCC we know there are 6 faces and 8 corners so per unit cell ther are 4 atoms as follow

= (8 corners *1/8) +(6faces *1/2)

= 4 atoms

So 1/4 fraction of the volume of each corner atom is actually within the volume of a face-centred cubic unit cell, so answer is

C. 1/4

2) We know that the critical temperature is the temperature and above this temp the vapor cannot gets liquefied. So answer is

A. the temperature above which a gas cannot be liquefied

3) We know that as we increase or decrease the equilibrium constant value cell potential also decrease. We also know in the equilibrium constant only aqueous and gas phase included and no any effect of solid, so when we added more tin metal to the anode compartment then there is no any effect on cell potential, so answer is –

A. addition of more tin metal to the anode compartment

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.