True or False: Simple covalent substances have low melting points because the covalent bonds within the molecules are weak and easy to break.

A substance that is brittle, has a high melting point, and only conducts electricity when dissolved in water is most likely a(n) __________ substance.

Which of the following describes the importance of mole-based calculations in 'Green Chemistry'?

In a molecule, individual bond dipoles may cancel out if the molecule has a __________ geometry, making the molecule non-polar overall. In a similar conceptual way, the properties of a metal are changed when the __________ of the lattice is disrupted by alloying.

Which of the following is a common reason why the actual yield of a chemical reaction is often lower than the theoretical yield?