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| Questão | Responda |
| Why do ionic compounds have high melting points? | It takes a lot of energy to break the many strong ionic bonds which hold a giant ionic lattice together. So ionic compounds have high high melting points. They are all solids at room temperature. |
| Why do ionic compounds conduct electricity when we melt them or dissolve them in water? | Because their ions can the move freely around and carry charge through the liquid. |
| Which type of substances has low melting points and boiling points? | Substances made up of simple molecules have low melting points and boiling points. |
| Why do simple molecule substances have low melting points and boiling points? | The Forces between simple molecules are weak. These weak intermolecular forces explain why substances made of simple molecules have low melting and boiling points. |
| Why don't these substances conduct electricity? | Simple molecules have no overall charge, so they cannot carry electrical charge. Therefore substances made of simple molecule cannot conduct electricity. |
| Why is diamond hard and graphite slippery? | Graphite has no covalnet bonds between its layer. This means they can slide over each other, making the graphite soft and slippery. The atoms in diamond have a different structure and cannot slide like this. So diamond is a very hard substance. |
| Why can graphite conduct electricity? | Because of the deloocalised electrons along its layers. |
| What is a Fullerence? | Form of the element carbon that can form a large cage-like structure, based on hexagonal rings of carbon atoms. |
| Why can we bend and shape metals? | Because the layers of atoms in a giant metallic structure can slide over each other. |
| Why are alloys harder than pure metals? | In alloys the layers cannot slide so easily because atoms of other elements change the regular structure making it harder than pure metals. |
| Why do metals allow electricity and heat to pass through them? | Delocalised electrons in metals enable electricity and heat to pass through the metal easily. |
| What are shape memory alloy? | They are metals which can return to their original shape by heating after it has been deformed. |
| Do the properties of polymers depend on the monomers we use? | Yes |
| Can changing reaction conditions modify the polymers that are made? | Yes |
| What are thermosetting and thermosoftening polymers? | Thermosetting polymers will not soften but will eventually char(burn) if heated very strongly. Thermosoftening polymers will soften or melt easily when heated. |
| What is nanoscience? | Is the study of small particles that are between 1 and 100 nanometres in size. |
| What are the potential benefits with nanoscience? | It can be used in medicines. |
| What are the potential risk with nanoscience? | Breathing in these tiny particles could cause damage to the lungs. |
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