A blacksmith heated an iron bar to 1445 °C. The blacksmith then tempered the metal by
dropping it into 42 800 cm of water that had a temperature of 22 °C. The final temperature of
the system was 45 °C. What was the mass of the bar?

beta decay is the answer

c.

explanation:

the answer is na (sodium)

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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