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In company with the learned

London yesterday:  hot and fuggy.  But we marched over Hungerford Bridge and found our way to Burlington House. 167 more words

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1.45 explain how the uses of diamond and graphite depend on their structures, limited to graphite as a lubricant and diamond in cutting.

Diamond

  • Cutting tool because of it’s rigid, trigonal structure and tight bonds

Graphite

  • Lubricant, because the graphite in the atoms form layers and layers are able to slide over each other…
  • 15 more words
Chemistry

1.44 draw diagrams representing the positions of the atoms in diamond and graphite

Diamond

  • Allotrope of carbon
  • Electric configuration: 2.4
  • Melting point: 355°c
  • Diamonds have no free electrons to carry electrical current

Graphite

Chemistry

1.36 describe an ionic crystal as a giant three-dimensional lattice structure held together by the attraction between oppositely charged ions

  • Ionic crystals are 3D lattice structures held together by electrostaticity.
  • Key term: electrostaticity / electrostatic force is the force/act of attraction/repulsion in molecules
  • This is present in ionic compounds as the ions are strongly attracted to each other…
  • 22 more words
Chemistry

1.35 understand the relationship between ionic charge and the melting point and boiling point of an ionic compound

  • The higher the charge of the ions, the higher the melting points
This is a paper 2, triple science fact.
Chemistry

1.26 calculate percentage yield

percentage yield = actual yield / theoretical yield

Actual yield is always lower than theoretical yield. Why?

  • Human error
  • Lost of product due to evaporation…
  • 18 more words
Chemistry