1.10.3 Trends in reactivity and properties down the group

• What is the atomic number of Lithium (Li)?

  3
• What is the atomic number of Francium (Fr)?

  87
• What trend is observed in the reactivity of alkali metals as you move down Group 1?

  Reactivity increases down the group
• Why do the alkali metals have such high reactivity?

  They have a single valence electron that is easily lost
• How does the ionization energy trend relate to the periodic table group and period trends?

  • Ionization energy increases from left to right across a period (same valence electrons)
  • Ionization energy decreases down a group (increasing atomic radius)
• How does ionization energy change down Group 1?

  It decreases down the group
• What happens when alkali metals react with water?

  They become highly reactive and lose electrons
• How does the reactivity of alkali metals with water change down Group 1?

  • Reactivity increases down the group
  • Lithium reacts calmly
  • Sodium reacts vigorously with bubbling
  • Potassium reacts explosively
• What contributes to the increasing size of alkali metals down Group 1?

  The increase in the number of electron shells
• How does potassium react with water?

  Explosively
• How does the electron configuration of alkali metals affect their chemical behavior?

  It leads to high reactivity due to one valence electron
• What physical property do alkali metals share?

  They are all soft metals
• What is the trend shown in the periodic table image?

  • The atomic radius decreases from left to right across a period (row) in the periodic table.
  • The atomic radius increases from top to bottom down a group (column) in the periodic table.
• What happens to electrons as atomic radius increases in Group 1?

  Electrons are held less tightly.
• Why does atomic radius increase down Group 1?

  Atoms gain additional electron shells
• What is the relationship between atomic radius and melting points in alkali metals?

  Lower melting points result from increased atomic radius.
• What are the two categories shown on the y-axis of the graph?

  male, female
• What does the arrow in the periodic table indicate about electronegativity?

  It shows the trend of electronegativity changes
• What happens to atomic radius as you move down Group 1?

  Atomic radius increases
• What is the periodic trend shown in the image?

  Ionization energy
• How does the outer shell arrangement of alkali metals change as you move down Group 1?

  The outer shell arrangement remains the same
• What does the image indicate about the trend of ionization energy across the periodic table?

  Ionization energy increases from left to right across the periodic table
• What does the purple diagonal arrows in the diagram indicate about non-metallic and metallic character?

  • Non-metallic character increases from bottom to top
  • Metallic character increases from top to bottom
• How do additional electron shells affect atomic radius?

  They increase the distance from the nucleus
• What factors influence the ionization energy of an element?

  • Nuclear charge (protons)
  • Electron configuration
  • Atomic radius
• What is the element with the largest atomic radius in the periodic table shown?

  Cs
• Why do alkali metals have similar chemical properties?

  They have the same outer shell arrangement
• What happens to the number of electron shells as you move down Group 1?

  The number of electron shells increases
• If an element has a high ionization energy, what does this indicate about its reactivity?

  The element is less reactive
• What trend occurs in melting and boiling points down Group 1?

  They decrease down Group 1.
• What happens to alkali metals when they react with water?

  They lose their outer electron to form +1 ions
• What is the relationship between atomic radius and ionization energy?

  Increasing atomic radius leads to lower ionization energy
• What are the key features of the periodic trend of electronegativity shown in the image?

  • Electronegativity increases from left to right across a period (row)
  • Electronegativity decreases from top to bottom down a group (column)
  • Electronegativity is highest for the halogens (group 17) and lowest for the alkali metals (group 1)
• Where are alkali metals located in the periodic table?

  Leftmost column
• What is the trend of electronegativity in the periodic table?

  • Increases from left to right
  • Decreases from top to bottom
• Why does ionization energy decrease down Group 1?

  Atoms get larger, outer electron is further away
• If an element has a high electronegativity, what can you infer about its chemical reactivity?

  It will be highly reactive and form strong bonds with other elements
• What is the electron configuration of alkali metals?

  One valence electron in outer shell
• Why are alkali metals considered very reactive?

  They have one electron in their outer shell
• What is electronegativity?

  Measure of an atom's electron attraction