Structure And Bonding Of Carbon
Visão Geral
Sharpen a pencil and you are holding one of the softest solids in the laboratory. Look at a ring set with a diamond and you are looking at the hardest natural material on Earth. Yet nothing separates them at the level of the atom. Both are pure carbon: the same element, six protons in every nucleus, no impurity that matters. What differs is how the atoms are joined up, and that turns out to be everything.
This lesson takes that difference apart. You will count the bonds each carbon atom makes in a diamond and in a flake of pencil lead, hunt down the one spare electron that lets a pencil line carry a current, and work out why sheets held to each other by almost nothing are exactly what a lubricant needs. Then you will meet the carbon structures chemists have built since 1985: hollow cages of sixty atoms, sheets a single atom thick, and tubes stiff enough to be worth putting inside a tennis racket.
Objetivos
- The element carbon can form four covalent bonds.
- In diamond, each carbon atom forms four covalent bonds with other carbon atoms in a giant covalent structure, so diamond is very hard.
- In graphite, each carbon atom bonds to three others, forming layers. The layers are free to slide over each other because there are no covalent bonds between the layers and so graphite is soft and slippery. Students should be able to explain the properties of graphite in terms of weak forces between the layers.
- In graphite, one electron from each carbon atom is delocalised. These delocalised electrons allow graphite to conduct heat and electricity. Students should realise that graphite is similar to metals in that it has delocalised electrons.
- Carbon can also form fullerenes with different numbers of carbon atoms. Fullerenes can be used for drug delivery into the body, in lubricants, as catalysts, and in nanotubes for reinforcing materials, eg in tennis rackets. Students are only required to know that the structure of fullerenes is based on hexagonal rings of carbon atoms.
Mapa mental
Este tema esta mapeado para mostrar como as ideias se ligam.
Abra o mapa mental na aplicacao
Nota de Aula
Apontamento completo disponivel na aplicacao Green Bridge
Instale a aplicacao Green Bridge CBT no telemovel ou computador para aceder a biblioteca IGCSE completa: exames anteriores, criterios de correcao, mapas mentais, cartoes de estudo e licoes em audio.
Avaliação da Lição
Parabéns por concluir a lição em Structure And Bonding Of Carbon. Agora que você explorou o conceitos e ideias-chave, é hora de colocar seu conhecimento à prova. Esta seção oferece uma variedade de práticas perguntas destinadas a reforçar sua compreensão e ajudá-lo a avaliar sua compreensão do material.
Irá encontrar uma mistura de tipos de perguntas, incluindo perguntas de escolha múltipla, perguntas de resposta curta e perguntas de redação. Cada pergunta é cuidadosamente elaborada para avaliar diferentes aspetos do seu conhecimento e competências de pensamento crítico.
Use esta secção de avaliação como uma oportunidade para reforçar a tua compreensão do tema e identificar quaisquer áreas onde possas precisar de estudo adicional. Não te deixes desencorajar pelos desafios que encontrares; em vez disso, vê-os como oportunidades de crescimento e melhoria.
- In graphite, how many other carbon atoms is each carbon atom covalently bonded to? A. One B. Two C. Three D. Four Answer: C
- Why is graphite soft and slippery? A. The covalent bonds within each layer are weak B. Only weak forces hold one layer to the next C. The carbon atoms are held together by ionic bonds D. Graphite contains delocalised electrons Answer: B
- Why does diamond not conduct electricity? A. Its atoms are held together by weak forces B. All four outer electrons of each carbon atom are used in covalent bonds C. It is transparent and colourless D. Its carbon atoms carry no charge Answer: B
- Which statement about fullerenes is correct? A. Their structure is based on hexagonal rings of carbon atoms B. They are giant covalent structures with no fixed formula C. Every fullerene contains exactly 12 carbon atoms D. Each carbon atom in a fullerene forms four covalent bonds Answer: A
- Graphite is similar to a metal because it: A. is shiny and can be bent into shape B. conducts electricity using delocalised electrons C. reacts with dilute acids to give hydrogen D. forms positive ions in solution Answer: B
Resolva estas questoes na aplicacao
Resolva estas questoes na aplicacao
Livros Recomendados
Pratique Questões Simuladas
Quer praticar questões simuladas sobre Structure And Bonding Of Carbon? Descarregue a aplicação Green Bridge CBT para aceder a questões simuladas e avaliações completas sobre este tópico.
Descarregar a aplicação na Google Play Store
Tudo o que precisas para te destacares no JAMB, WAEC e NECO.
