In the following multiple-choice questions, choose the most appropriate ONE answ
ID: 877900 • Letter: I
Question
In the following multiple-choice questions, choose the most appropriate ONE answer.
1. In a one component system when degrees of freedom are zero, how many phases coexist at equilibrium?
(a) 2
(b) 3
(c) 4
(d) 5
2. How many degrees of freedom does a four component system have, when four phases coexist at equilibrium if pressure is not constant?
(a) 2
(b) 3
(c) 4
(d) 5
3. What is the atomic fraction of zinc in aluminum for a two-component alloy containing 10 wt.% zinc? Atomic weight for zinc is 65.39 g/mol and that of aluminum is 26.9 g/mol. (a)
(a) 4.37
(b) 2.52
(c) 10.5
(d) 15.35
4. Which one of the following statements is false in the context of isomorphous two-component phase diagrams?
(a) Congruent melting alloy freezes over a range of temperatures
(b) Congruent melting alloy can have highest melting point of any alloy composition in the binary isomorphous diagram.
(c) Congruent melting alloy can have lowest melting point of any alloy composition in the binary isomorphous diagram.
(d) Congruent melting alloy may have highest or lowest melting point of any alloy composition depending on the nature of components that have isomorphous phase diagram.
5. Which one of the following is the correct representation of the Gibbs phase rule applicable to two component temperature-composition phase diagrams?
(a) F = C – P + 2
(b) F = C – P + 1
(c) F = C + P + 1
(d) F = C – P + 3
6. Which one of the following is applicable to the components A and B that form an ideal isomorphous binary phase diagram?
(a) Bond energy of A-B bonds is equal to the bond energy of A-A bonds in liquid state but not in solid state.
(b) Bond energy of A-B bonds is lower than bond energy of A-A bonds as well as bond energy of B-B bonds in liquid state but nor in solid state.
(c) Bond energy of A-B bonds is equal to the average of the bond energies of A-A and B-B bonds in both liquid state and solid state
(d) Bond energy of A-B bonds is higher than bond energy of A-A bonds as well as bond energy of B-B bonds in both liquid and solid states
Explanation / Answer
1) F= C-P+2
0= 1-P+2
P=3
ANSWER IS B
2) F =C-P+2
= 4-4+2
F=2
ANSWER IS A
5) F= C-P+1
ANSWER IS B
6
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.