For each solute, identify the better solvent: water or carbon tetrachloride
na2s, c6h6, ch3oh, br2

In water solvent:

Na₂S and CH₃OH

In carbon tetrachloride solvent:

C₆H₆ and Br₂

Explanation:

Using : Like dissolves like

Polar substances dissolve in polar and non polar substance in non polar.

Since water is polar and carbon tetrachloride is non polar.

Na₂S, sodium sulfide is an ionic compound and thus it best dissolves in a polar solvent which is water.

C₆H₆, benzene is non polar and dissolves in carbon tetrachloride.

CH₃OH, methanol which is polar and dissolves in water.

Br₂, bromine gas is non polar and dissolves in carbon tetrachloride.

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.