science

• what are the group 7 elements called?

  the halogens
• do the melting points of the group 7 elements increase or decrease?

  increase
• as you go down the group, the colour of the element darkens

  (group 7)
• how many outer electrons in the group 7 elements

  7
• all of the group 7 elements are diatomic
• nonmetals are covalent bonds

  metals are ionic bonds
• group 7 elements have low melting points because weak intermolecular forces are easier to overcome
• the group 7 elements need to gain one more electron to have a full outer shells
• what are the group 1 elements called?

  the alkali metals
• as you down down the group, what happens to the size of the atoms?

  Increases
• what colour does lithium oxide burn?

  crimson
• what colour does sodium oxide burn?

  yellow
• what colour does potassium burn?

  Lilac
• what are the group 0 elements also known as?

  the noble gases
• how many outer electrons in the group 0 elements

  0 in most, 2 in helium as it only has an inner shell
• having a full outer shell means the element is very stable and unlikely to react with other elements
• the noble gases are typically found as monatomic (single atoms)
• when did mendeleev arrange the 50 known elements into a table?

  1869