7 how many isomeric alkanes of the molecular formula

7. How many isomeric alkanes of the molecular formula C
5
H
12
are there?
(a) 1 (b) 2 (c) 3 (d) 4 (e) 5
8. Dehydration of an alcohol leads to the formation of an _____ .
9. The organic starting materials for the preparation of an ester could be _______ .
10. Hydrolysis (saponification) of a fat would yield ______ .

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II. Essay. Answer the following questions in three to five sentences only. Be guided with the rubric on the next page for
the proficiency of your answer. (10 pts)
1. Why are short-chain alkanes like methane and butane serve as good fuels?
2. Ethanol and dimethyl ether have the same molecular formula C
2
H
6
O. Ethanol is liquid at room temperature while
dimethyl ether is gas. How is this possible?
PREPARED: CHECKED / NOTED:
DONNA A. DE SAGUN MA VERLA AFRICA ALVARAN
Teacher II Principal II
Scoring Rubrics for Essay/Short-answer questions
POINTS DESCRIPTION
5
Answers are comprehensive, accurate and complete. Key ideas are clearly stated and well
supported
4 Answers are accurate and complete. Key ideas are clearly stated and well supported.
3 Answers are accurate and complete. Key ideas are stated and supported.
2 Answers are not comprehensive or completely stated. Key points are addressed but not well
supported.
1 Answers are partial or incomplete. Question not adequately answered.