(Q1) State weather each of the following compounds is ionic or covalent: Q2) A: what is meant by a covalent bond? How does this bond hold two atoms together?

Q3) Draw dot-and-cross diagrams (showing outer shell electrons
Only) to show the covalent bonding in

Q4) Explain why carbon dioxide sublimes at -78.5°C but Diamond sublimes at around 4000°C.

Q5) Hexane has the formula C6H14, it is a liquid at room temperature.

Q6) Explain the following in terms of structure and bonding.

Why is nh3 classified as a polar molecule

The small bags of silica gel you often see in a new shoe box are placed there to control humidity. despite its name, silica gel is a solid. it is a chemically inert, highly porous, amorphous form of sio2. because water vapor readily adsorbs onto the surface of silica gel, it acts as a desiccant. despite not knowing mechanistic details of the adsorption of water onto silica gel, from the information provided you should be able to make an educated guess about the thermodynamic characteristics of the process. predict the signs for δg, δh, and δs for the adsorption of water.

What is the most common reason for matter changing its state?