Question

Choose all the answers that are true about water.? 1. Water dissolves substances that are polar (polar covalent bonds). 2. Water dissolves substances that are non-polar (non-polar covalent bonds) 3. water is an excellent solvent. 4. Water dissolves substances with ionic bonds, such as NaCl.

Answer 1

1. Water dissolves substances that are polar (polar covalent bonds) because polar molecules are dipoles (have separation of partial positive and partial negative charges). Water itself as a dipole forms dipole-dipole interactions with polar molecules. This means water likes hanging out other polar molecules almost as much as it likes water molecules being around other water molecules.

3. Water is an excellent solvent because of its high dielectric constant (how easy a material can be polarized by imposing an electric field). Because of this high dielectric constant water can dissolve more substance than any other liquid, that is why it is also called a universal solvent.

4. Water dissolves substances with ionic bonds, such as NaCl. These ionic compounds dissociate into their respective cations and anions like Na+ and Cl^- . Oxygen atoms with partial negative charges of water molecules surround the Na+ and stabilize it. Hydrogen atoms with partial positive charges surround the Cl^- ion and stabilize it.