Sucrose and naphthalene are both organic molecules. Did you find significant differences in their solubilities

Naphtalene is very unlikely to get dissolved in water as it is nonpolar.

Sucrose is very likely to get dissolved in water as it is polar at the oxygen-to-hydrogen bonds.

Explanation:

Hello,

In this case, naphtalene (C₁₀H₈) is constituted by both carbon-to-carbon and carbon-to-hydrogen bonds only as it is an aromatic hydrocarbon which is highly nonpolar due to the low-polarity of the C-H bond, therefore, it is very unlikely to get dissolved in water. On the other hand, sucrose (C₁₂H₂₂O₁₁) has oxygen-to-hydrogen bonds which are highly polar, for that reason, it is able to get dissolved in water via hydrogen bonds.

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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.