Here's why:
* Polarity: Polar molecules have a separation of electric charge, creating a positive and negative end. Water is a great example, with its oxygen atom being slightly negative and its hydrogen atoms being slightly positive.
* Salt and Sugar: Both salt (NaCl) and sugar (sucrose) are polar molecules. Salt is an ionic compound, forming strong electrostatic attractions between positive sodium ions (Na+) and negative chloride ions (Cl-). Sugar has a complex structure with many polar hydroxyl groups (-OH) that also create attractive forces.
* Kerosene: Kerosene is a nonpolar hydrocarbon. It's made of long chains of carbon and hydrogen atoms, with no significant separation of charge.
The Rule: "Like dissolves like." This means polar substances dissolve best in other polar substances, and nonpolar substances dissolve best in nonpolar substances.
Why it doesn't work: The strong attractive forces between the polar salt and sugar molecules are much stronger than the weak interactions they could form with nonpolar kerosene molecules. Therefore, they can't break apart and disperse within kerosene.
In contrast: Water is a polar solvent, which is why salt and sugar readily dissolve in it. The water molecules can interact with the charged or polar parts of salt and sugar molecules, effectively pulling them apart and dispersing them throughout the water.
