What mass of NH4Cl will dissolve in 100g (or 100mL) of water at 50 degrees?

i think it's c. i'm not sure but i think so.

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.

if it's not useful, feel free to report for mistake in answer.

you didnt put any of the following

the answer is 0.42 is that is an option. this question provides no info