Group 1 - chemical reactions with oxygen and chlorine

• What do elements in the same group of the periodic table show trends in?

  Physical properties, such as boiling point
• Why do elements in the same group have similar chemical properties?

  They have the same number of electrons in their outer shell
• What is the first vertical column of elements in the periodic table called?

  • Alkali metals
  • Also known as Group 1
  • Starts with lithium and ends with francium
• What happens when group 1 elements react with oxygen?

  They form metal oxides
• What is formed when sodium reacts with oxygen?

  Sodium oxide
• Write the balanced equation for the reaction of sodium with oxygen.

  $4Na(s) +$$O_2(g) \rightarrow 2Na_2O(s)$
• How does the reactivity of group 1 elements change down the group?

  The reactivity increases down the group
• Why does rubidium become white more quickly than lithium when exposed to air?

  Rubidium is more reactive because it is below lithium in group 1
• What do group 1 elements form when they react with chlorine?

  They form chlorides
• What is the state of chlorides formed by group 1 elements at room temperature?

  They are white solids
• Write the balanced equation for the reaction of potassium with chlorine.

  $2K(s) +$$Cl_2(g) \rightarrow 2KCl(s)$
• What happens to the outer electron of a group 1 element during a reaction?

  It is lost to form a positively charged ion
• How does the size of atoms change down group 1?

  The atoms become larger
• What happens to the force of attraction between the nucleus and the outer electron as you go down group 1?

  The force of attraction decreases
• Why is the outer electron lost more easily in larger atoms of group 1 elements?

  Because it is further from the nucleus
• What are the key trends in reactivity for group 1 elements?

  • Reactivity increases down the group
  • Atoms become larger
  • Outer electron is lost more easily