For the conversion of ice to water at 0°c and 1 atm,1.δg is negative,δh is negative, and δs is positive.2.δg is zero, δh is positive, and δs is positive.3.δg is positive, δh is negative, and δs is positive.4.δg is zero, δh is positive, and δs is negative.

2. ΔG is zero, ΔH is positive, and ΔS is positive

Explanation:

When the ice is being converted to water ate 0ºC and 1 atm, there is an equilibrium between the solid and the liquid. At the equilibrium point, ΔG (the free energy) is zero. It is negative for spontaneous reactions and positive for nonspontaneous reactions.

For the phase change happens, the ice must absorb heat from the surroundings, so it's an endothermic reaction, and because of that ΔH (the enthalpy) must be positive. It is negative for exothermic reactions.

In the liquid state, the molecules have more energy and the randomness is higher than the solid-state. The entropy (S) is the measure of the randomness, so if it's increasing, ΔS must be positive.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-