Question

what force in liquids causes surface tension?
covalent forces
intermolecular forces
intramolecular forces
ionic forces
done

Explanation:

To determine the force causing surface tension in liquids, we analyze each option:

• Covalent forces are within a molecule (e.g., bonding atoms in a molecule), not between molecules, so they don't cause surface tension.
• Intermolecular forces are the forces between molecules. In liquids, the cohesive intermolecular forces (like hydrogen bonding, dipole - dipole, or London dispersion forces) between liquid molecules at the surface pull the surface molecules inward, creating surface tension.
• Intramolecular forces are the forces within a molecule (e.g., covalent bonds holding atoms in a molecule together) and do not act between different molecules to create surface tension.
• Ionic forces are a type of intramolecular or inter - ionic (in ionic compounds) force and are not the primary force for surface tension in most liquids (which are often molecular, not ionic).

Answer:

B. intermolecular forces