1. The unequal sharing of electrons in a water molecule occurs because oxygen is more electronegative than hydrogen. This means oxygen pulls the shared electrons closer to itself, creating a partial negative charge (δ-) on the oxygen atom and partial positive charges (δ+) on the hydrogen atoms. This results in a bent molecular shape and a net dipole moment, making water polar.
2. Water acts as an excellent solvent for polar and ionic substances because its polarity allows it to surround and separate solute particles. For example, in living organisms, water dissolves nutrients like glucose and ions such as sodium and potassium, enabling their transport through the bloodstream and into cells for metabolic processes.
3. Adhesion is the attraction between water molecules and other substances, while cohesion is the attraction between water molecules themselves. In plants, adhesion helps water stick to the walls of xylem vessels, and cohesion allows water molecules to pull each other upward through the plant via capillary action. Together, these properties enable water to travel from roots to leaves against gravity.
4. The property shown is surface tension. Water’s hydrogen bonds create strong cohesive forces between molecules at the surface, forming a “skin” that resists external force. This allows small insects like water striders to walk on water without breaking the surface, as the hydrogen-bonded network supports their weight.
Parent Tip: Review the logic above to help your child master the concept of properties of water worksheet answers.
