When 0.2mol of calcium reacts with 880g of water 2.24l of hydrogen gas form at stp how would the amount of hydrogen produced change if the volume of water was decreased to 440ml 400g?

The volume of hydrogen produced would be the same.

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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