Question 12:
Which of the following is an alkanoic acid?
A. Ethanoic acid
B. Sulphuric acid
C. Hydrochloric acid
D. Carbonic acid
Question 14:
Which of the following pairs can represent the respective empirical formula and
molecular formula of a certain compound?
A. CH and CH4
B. CH and C6H6
C. CH2 and C2H2
D. CH3 and C3H6
Question 15:
Which of the following compounds have the same empirical formula?
(1) But-2-ene
(2) Propane
(3) Ethene
A. (1) and (2) only
B. (1) and (3) only
C. (2) and (3) only
D. (1), (2) and (3)
Question 16:
Which of the following statements concerning homologous series is INCORRECT?
A. Members of a series have identical chemical properties.
B. Members of a series have the same general formula.
C. Each member differs from the next by a −CH2− group.
D. Members of a series show a gradual change of physical properties.
5
Question 17:
Which of the following is a hydrocarbon?
A. Petroleum
B. Oct-3-ene
C. Ethanol
D. A mixture of hydrogen and carbon
Question 18:
Which of the following names are INCORRECT?
(1) But-3-ene
(2) 1-bromo-propan-3-ol
(3) 2,3-chlorobutane
A. (1) and (2) only
B. (1) and (3) only
C. (2) and (3) only
D. (1), (2) and (3)
急~CHEM. MC
2010-11-04 7:05 am
回答 (2)
2010-11-04 9:53 am
✔ 最佳答案
Question 12:The answer is: A. Ethanoic acid
Alkanoic acid contains a alkyl group and a -COOH group. Hence, ethanoic acid (CH3COOH) is an alkanoic acid.
=====
Question 14:
The answer is: B. CH and C6H6
Empirical formula = CH
molecular formula = (CH)6 = C6H6
=====
Question 15:
The answer is: B. (1) and (3) only
(1) CH3CH=CHCH3, molecular formula = C4H8, empirical formula = CH2
(2) CH3CH2CH3, molecular formula = C3H8, empirical formula = C3H8
(3) CH3=CH2, molecular formula = C2H4, empirical formula = CH2
=====
Question 16:
The answer is: C. Each member differs from the next by a −CH2− group.
This is the definition of homologous series.
=====
Question 17:
The answer is: B. Oct-3-ene
A hydrocarbon is a pure compound containing hydrogen and carbon atoms only.
B is CH3CH2CH=CH(CH2)3CH3, which is a hydrocarbon.
A is a mixture of hydrocarbons, but not a hydrocarbon. C is an alcohol. D is a mixture.
=====
Question 18:
The answer is: D. (1), (2) and (3)
(1) CH3CH2CH=CH2 should be named as but-1-ene.
(2) BrCH2CH2CH2OH should be named as 3-bromopropan-1-ol.
(3) CH3CHClCHClCH3 should be named as 2,3-dichlorobutane.
2010-11-05 00:07:50 補充：
Correction for Question 16:
The answer is: A. Members of a series have identical chemical properties.
2010-11-05 00:08:30 補充：
A: Incorrect. Their chemical properties are similar, but not identical.
B: Correct. e.g. the general formula for acyclic alkanes are CnH2n+2.
C: Correct. It is the definition of homologous series.
D: Correct. They have the same functional group and the alkyl groups gradually increase in size.
參考: 土扁, adam, adam
2010-11-04 10:13 am
16 is wrong. look carefully at question ---- find the INCORRECT one.
should be A.
should be A.
收錄日期: 2021-04-16 11:51:33
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20101103000051KK01707