What mass of aluminium chloride can be obtained when 0.48mols of aluminium is completely reacted with dilute hydrochloric acid? Equation for this reaction:
2Al + 6HCl 2AlCl3 + 3H2

Explanation:

we will do ratio method

Aluminum chloride :  Aluminum

2                               :      2

0.48                          :      x

(cross multiply)

0.48 x 2 / 2 = 0.48 moles of aluminum  

mass = 1 mole of aluminum chloride x moles

mass = 133.33 x 0.48

mass = 63.9984g (round off) = 64g

I hope this helps.

b.final

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.