In a laboratory experiment, a mixture of alkanes was separated into components by fractional distillation using the following apparatus - VCE - SSCE Chemistry - Question 20 - 2008 - Paper 1
Question 20
In a laboratory experiment, a mixture of alkanes was separated into components by fractional distillation using the following apparatus.
The first fraction collecte... show full transcript
Worked Solution & Example Answer:In a laboratory experiment, a mixture of alkanes was separated into components by fractional distillation using the following apparatus - VCE - SSCE Chemistry - Question 20 - 2008 - Paper 1
Step 1
A. fraction Y is more volatile than Z.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Volatility in distillation is typically determined by boiling points. Since fraction Y is collected after fraction X, it can be inferred that Y is indeed more volatile than Z, which is collected later.
Step 2
B. fraction Y has a higher molar mass than Z.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Molar mass often correlates with boiling points in hydrocarbons. However, the order of collection does not indicate that Y must have a higher molar mass; hence, this statement is not necessarily true.
Step 3
C. fraction X has a higher boiling point than Y and Z.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Since fraction X is collected first, it must have the lowest boiling point among the three fractions, confirming that it indeed has a higher boiling point than the fractions that follow.
Step 4
D. fraction Z has stronger covalent bonds in its molecules than X and Y.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Covalent bond strength does not directly affect the order in which fractions are collected. The properties of the different fractions may vary based on molecular structure rather than bond strength alone.