Car manufacturers and governments have been eagerly seeking a replacement for the automobile's main source of power, the internal-combustion engine. By far the most promising alternative source of energy for cars is the hydrogen-based fuel-cell engine, wh

The reading states that replacement of internal combustion engine by a hydrogen-based fuel cell engine is more suitable and provides three reasons of support. However, the lecture concerns the topic of replacement for the automobile's main source of power with an emphasis on the process of preparing hydrogen is not a solution to this problem , the speaker takes the time to explain why the three techniques described in the text are not reliable when trying to prove fuel cell engine is much more efficient. Because of this, the information presented in the lecture directly contradicts what is stated in the text.

First, the article claims that hydrogen can be derived from plentiful sources such as natural gas and water. The professor refutes this point by saying that even though hydrogen is present in water it is not easily available. He states that, to run the fuel cell, hydrogen must be obtained in purely liquid state and it needs advanced technology.

Second, the article posits that the byproduct of burning oil is carbon dioxide which harms the environment. However, the professor says that producing pure hydrogen would pollute the environment even more. According to the professor, gaining pure hydrogen requires lots of energy and the energy is generated by burning coal and oil. Hence, if the car do not pollute, factories would pollute.

Third, the reading says that this replacement will be economically beneficial. The professor opposes this point by explaining that fuel cell engine requires components made of expensive metal which is rarely available, that is platinum which is necessitate for chemical reaction that produces electricity.

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Essay Categories

with an emphasis on the process of preparing hydrogen is not a solution to this problem ,
with an emphasis on the process of preparing hydrogen which is not a solution to this problem ,

if the car do not pollute,
if the cars do not pollute,

platinum which is necessitate for chemical reaction
platinum which is necessary for chemical reaction

flaw:
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Attribute Value Ideal
Score: 22 in 30
Category: Good Excellent
No. of Grammatical Errors: 3 2
No. of Spelling Errors: 0 2
No. of Sentences: 12 12
No. of Words: 266 250
No. of Characters: 1370 1200
No. of Different Words: 145 150
Fourth Root of Number of Words: 4.039 4.2
Average Word Length: 5.15 4.6
Word Length SD: 2.68 2.4
No. of Words greater than 5 chars: 106 80
No. of Words greater than 6 chars: 85 60
No. of Words greater than 7 chars: 57 40
No. of Words greater than 8 chars: 35 20
Use of Passive Voice (%): 0 0
Avg. Sentence Length: 22.167 21.0
Sentence Length SD: 12.812 7.5
Use of Discourse Markers (%): 0.5 0.12
Sentence-Text Coherence: 0.348 0.35
Sentence-Para Coherence: 0.606 0.50
Sentence-Sentence Coherence: 0.084 0.07
Number of Paragraphs: 4 4