Group 1 (alkali metals) – lithium, sodium and potassium

• How many protons, neutrons and

  electrons does potassium have?

  19 protons and electrons and 20

  neutrons
• How do electrons exist in an atom?


  In shells.
• Element X is in group 1, period 6. What

  element is it?

  Caesium
• What is the electron configuration of a

  lithium ion?

  Just 2
• Group 1 metals

  Lithium, Sodium, Potassium,

  Rubidium, Caesium and Francium.
• How many electrons do Group 1 metals have in their outer shell?


  One.
• Properties of group 1 metals

  All the Group 1 elements are silvery-coloured metals. They are

  soft, and can be easily cut with a knife to expose a shiny surface

  which dulls on oxidation

  These elements are highly reactive metals. The reactivity

  increases on descending the Group from lithium to Caesium.

  There is a closer similarity between the elements of this Group

  than in any other Group of the periodic table.

  The alkali metals differ from other metals in several ways. They

  are soft, with low melting and boiling temperatures. They have

  low densities - Li, Na and K are less dense than water
• GROUP 1

  Group 1 in the periodic table contains the

  alkali metals.

  They all have 1 electron in their outer shell

  They are quite reactive metals

  They are soft metals
• Why do the metals get more reactive as they go down the group?

  As you go down Group 1 the

  atoms become larger and the

  outer electron is further from

  the nucleus.

  The force

  of attraction between the

  positively-charged nucleus and

  the negatively-charged outer

  electron becomes weaker, which

  is why the outer electron is

  more easily lost.
• How do the group 1 metals react with

  water?

  Lithium, sodium and potassium all react vigorously with

  water
• What does the reaction of group 1 metals with water produce?

  Hydrogen gas bubbles off, a metal hydroxide is formed

  which is a strong alkali
• Why are group 1 metals stored under oil?

  To prevent them reacting with the oxygen and water

  vapour in the air.
• Why are they called alkali metals?

  They form an alkali solution when in water
• Group 1 metals reaction with oxygen:


  Group 1 metals have to be kept in oil to not react with

  oxygen and water.

  When we cut them they are shiny. However, as they begin

  to react with oxygen in the air they begin to dull, forming

  a metal oxide.

  Metal + oxygen 🡪 Metal oxide

  Lithium + oxygen 🡪 lithium oxide

  Li + O2 🡪 Li2O

  We can also react these with oxygen by burning them.

  They form colourful flames
• Flame test on group 1 metals:

  Lithium - red

  Sodium - yellow

  Potassium - lilac