Group 1 - Alkali metals

• Name the group 1 metals

  Lithium, Sodium, Potassium, Rubidium, Caesium and Francium
• What physical properties do group 1 metals have?

  Low melting and boiling points compared to other metals

  Low density - Li , Na + K can float on water

  Very soft - can be cut with a knife
• What type of compounds can these Alkali metals form?

  Ionic compounds with non-metals; they lose their one outer electron so easily + they don't form covalent bonds
• Which test can you use to reveal the presence of group 1 metals?

  Flame tests
• Why are group 1 metals very reactive?

  They readily lose their single outer electron to form a 1+ ion with a stable electronic structure. The more readily a metal loses its outer electrons, the more reactive it is
• Which elements do these alkali metals react the most vigorously with?

  Water, oxygen and group 7 elements such as Chlorine
• Caesium ( being very reactive) can ignite spontaneously at room temperature
• What pattern do you notice as you go down the group?

  The melting and boiling points decrease
• As you go down the group, the atom's radius gets bigger. What does this mean for the outermost shell?

  It gets further away from the positive nucleus
• As the atom's radium gets bigger, the outermost shell gets further from the positive nucleus. How does this affect the attractive forces between the positive nucleus and the outer negative electron?

  The positive nucleus is the only thing holding the outermost electron in place so the increased distance weakens the attractive force between the positive nucleus and the outer negative electron. This means that the electron can be lost more easily, increasing the atoms reactivity
• What happens when an alkali metal is put in water?

  It tracks vigorously to produce a metal hydroxide and hydrogen gas.
• What happens when an alkali metal reacts with Chlorine gas?

  It will react vigorously when heated in chlorine gas and in this case they from white metal chloride salts
• What happens when alkali metals react with oxygen?

  The form metal oxides, however the type of oxide they form will depend on the particular metal