physical & chemical properties

• What happens to atomic radius down group 2?

  Atomic radius increases
• Why does atomic radius increase down group 2?

  More inner electron shells are added
• How does increased shielding affect atomic radius in group 2?

  It decreases electrostatic attraction to outer electrons
• What is the trend of melting points down group 2?

  Melting points generally decrease
• What anomaly occurs in the melting point trend of group 2?

  Magnesium shows an anomaly
• Why do melting points decrease down group 2?

  Ionic radius of the metal ion increases
• How does the ionic radius affect melting points in group 2?

  Delocalised electrons are further from nuclei
• What happens to the energy needed to break metallic bonds down group 2?

  It decreases
• What ions do group 2 elements form?

  2+ ions
• How do group 2 elements form 2+ ions?

  By losing their two outermost electrons
• What is the electron configuration of Be2+?

  1s2
• What is the electron configuration of Mg2+?

  1s2 2s2 2p6
• What is the electron configuration of Ca2+?

  1s2 2s2 2p6 3s2 3p6
• What does the loss of two electrons result in for group 2 elements?

  A stable noble gas electron configuration
• What happens to first ionisation energy down group 2?

  It decreases
• Why does first ionisation energy decrease down group 2?

  Atomic radius increases and shielding increases
• How does nuclear charge affect ionisation energy down group 2?

  Nuclear charge increases but effect is weaker
• What is the relationship between atomic radius and ionisation energy?

  Increased atomic radius leads to lower ionisation energy
• How does reactivity change down group 2?

  Reactivity increases
• Why does reactivity increase down group 2?

  Atomic radius and electron shielding increase
• What is the reaction of a group 2 metal with cold water?

  M(s) + H2O(l) ➔ M(OH)2(aq) + H2(g)
• What is the reaction of calcium with water?

  Ca(s) + 2H2O(l) ➔ Ca(OH)2(aq) + H2(g)
• What happens to calcium in its reaction with water?

  Calcium is oxidised from 0 to +2
• What is the reaction of a group 2 metal with oxygen?

  2M(s) + O2(g) ➔ 2MO(s)
• What is the reaction of calcium with oxygen?

  2Ca(s) + O2(g) ➔ 2CaO(s)
• What happens to calcium in its reaction with oxygen?

  Calcium is oxidised from 0 to +2
• What happens to oxygen in its reaction with calcium?

  Oxygen is reduced from 0 to -2