What is wrong with the following statement? Hal says that his teacher is solely responsible for preventing laboratory accident.

Hal is wrong because the teacher can instruct the student, but no make all the choices in a lab.Students must always wear ppe (personal protection equipment) , use proper lab protocol, and conduct themselves in a responsible manner. It is NOT the work of a teacher to ensure lab safety, but in fact the responsibility of said students.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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