Answer: b. 
is positive and 
is positive.
Explanation:-
As the temperature of the pack drops, the energy has been absorbed from the pack for dissolution of 
in water. Thus as the energy has been absorbed in the reaction, the reaction is endothermic and the change in enthalpy i.e. is positive.
The entropy is the measure of degree of randomness. The entropy increases when the randomness increases and the entropy decreases when the randomness decreases. When a substance dissolves in water, it dissociate into ions and hence the randomness increases thus the change in entropy i.e. is positive.
In chemistry, a solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent.
Molality
is one way of expressing concentration of a solute in a solution. It is expressed
as the mole of solute per kilogram of the solvent. To calculate for the
molality of the given solution, we need to convert the mass of solute into
moles and divide it to the mass of the solvent.
<span>
Moles of HCl = 5.5 g HCl ( 1 mol HCl / 36.46 g HCl ) = 0.1509 mol HCl</span>
<span>
Molality = 0.1509 mol HCl / 200 g C2H6O ( 1 kg / 1000 g )
Molality
= 0.7543 mol / kg</span>
<span>The concentration in molality of hcl in a solution that is prepared by dissolving 5.5 g of hcl in 200.0 g of c2h6o is
0.7453 molal.</span>
