1.11 Group 1 (Alkali Metals)

• What are the group 1 elements known as?

  Alkali metals
• Which elements are included in the alkali metals group?

  Lithium, sodium, potassium, rubidium, cesium, and francium
• How do alkali metals differ from most other metals?

  They are relatively soft, have low densities, and low melting points
• What is the reactivity of alkali metals compared to other metals?

  They are much more reactive than other metals
• With which substances do alkali metals react vigorously?

  Water, oxygen, and group 7 elements such as chlorine
• What happens to the reactivity of alkali metals as you go down the group?

  The elements become more reactive
• Which alkali metal can ignite spontaneously at room temperature?

  Cesium
• What trend is observed in melting and boiling points as you go down the alkali metals group?

  Melting points and boiling points decrease
• Why doesn't sodium in table salt catch fire when sprinkled on food?

  Because it is already in a stable ionic compound form
• Why are alkali metals so reactive?

  They have one electron in their outermost shell that they can easily lose
• What happens to an alkali metal when it loses its outer electron?

  It becomes a one positive ion
• How does the atomic radius affect the reactivity of alkali metals?

  A larger atomic radius weakens the attractive force on the outer electron
• What does the term reactivity refer to?

  How easily atoms can lose or gain electrons
• What type of compounds do alkali metals typically form with non-metals?

  Ionic compounds
• What is the reaction of sodium with chlorine gas?

  Sodium plus chlorine forms sodium chloride
• What do alkali metals form when they react with water?

  A metal hydroxide and hydrogen gas
• What is the reaction equation for sodium reacting with water?

  Sodium + water → sodium hydroxide + hydrogen
• What happens to the energy released in reactions as you go down the alkali metals group?

  The reactions release more energy
• What do alkali metals form when they react with oxygen?

  Metal oxides
• What is the oxide formed when lithium reacts with oxygen?

  Lithium oxide (Li₂O)
• What is the oxide formed when sodium reacts with oxygen?

  Sodium oxide (Na₂O)
• What oxides can potassium form when reacting with oxygen?

  Potassium can form potassium peroxide (K₂O₂) or potassium superoxide (KO₂)
• What are the general properties of alkali metals?

  • Soft
  • Low density
  • Low melting points
  • Highly reactive
• What are the reactions of alkali metals with water, chlorine, and oxygen?

  • Water: Produces metal hydroxide and hydrogen gas
  • Chlorine: Forms white metal chloride salts
  • Oxygen: Forms metal oxides
• What are the trends in reactivity and physical properties of alkali metals?

  • Reactivity increases down the group
  • Melting and boiling points decrease down the group
• What is the significance of ionic compounds formed by alkali metals?

  • Formed by donating electrons to non-metals
  • Generally white solids
  • Tend to dissolve in water to form colorless solutions
• What is a good study method for remembering alkali metal reactions?

  • Use flashcards to practice reactions and compounds