Using the following data, Compound Melting Point (C) ?Hfus (kJ/mol) Boiling Poin
ID: 1362327 • Letter: U
Question
Using the following data,
Compound
Melting Point (C)
?Hfus (kJ/mol)
Boiling Point (C)
?Hvap (kJ/mol)
HF
-83.11
4.577
19.54
25.18
HCl
-114.3
1.991
-84.9
17.53
HBr
-86.96
2.406
-67
19.27
HI
-50.91
2.871
-35.38
21.16
calculate Sfus and Svap for HF.
Determine the entropy change when 8.60 mol of HF(l) freezes at atmospheric pressure.
Compound
Melting Point (C)
?Hfus (kJ/mol)
Boiling Point (C)
?Hvap (kJ/mol)
HF
-83.11
4.577
19.54
25.18
HCl
-114.3
1.991
-84.9
17.53
HBr
-86.96
2.406
-67
19.27
HI
-50.91
2.871
-35.38
21.16
Explanation / Answer
part A )
i ) dSfus = Hfus/Tfus
dSfus = 4.577 / ( 273-83.11) = 0.024 kJ/mol *K
dSvap = 25.18 / (273 + 19.54) = 0.0861 kJ/mol*k
Part B )
dS = nH/T
dS = 8.60 * 4.577 kJ / 189.89
dS = 0.207 kJ/K
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.