Chemistry 4

• What are the Group 1 elements known as in the Periodic Table?

  Alkali metals
• What is a key property of Group 1 elements when freshly cut?

  They are shiny
• What is a common characteristic of alkali metals regarding their physical state?

  They are good conductors of heat and electricity
• How does the softness of alkali metals change down the group?

  They become softer and easier to cut
• Why must Group 1 metals be stored under oil?

  They react very readily with air and moisture
• What general trend occurs in density as you move down Group 1?

  Density decreases
• What do alkali metals react with to form a white powder?

  Air or water
• What happens to the melting point of alkali metals as you go down the group?

  Melting point increases
• How does reactivity change as you move down Group 1?

  Reactivity increases
• What is the density of water?

  1 g/cm³
• What is the balanced equation for sodium reacting with water?

  2Na(s) + 2H₂O(l) → 2NaOH(aq) + H₂(g)
• What is the most predictable reaction of Group 1 metals?

  The reaction with water
• How does sodium react with water?

  It reacts readily and rapidly
• What is produced when potassium reacts with water?

  Flammable hydrogen and hydroxide
• Why do Group 1 elements have similar chemical properties?

  Due to their outer shell electrons
• What does the general equation M → M+ + e- represent?

  The loss of an outer electron
• Why is potassium more reactive than sodium?

  It requires less energy to lose its outer electron
• What happens to the reactivity of alkali metals as you go down the group?

  It increases
• What is the trend in boiling points for Group 7 elements?

  Boiling points increase down the group
• What are the Group 7 elements known as?

  Halogens
• What color is fluorine gas at room temperature?


  Pale yellow
• What is the state of iodine at room temperature?

  Dark grey-black crystalline solid
• How do halogens react with metals?

  To form salts
• What happens to the reactivity of halogens as you go down the group?

  Reactivity decreases
• Why do halogens have similar chemical properties?

  They have seven electrons in their outer shell
• What is the general equation for halogens reacting with metals?

  X₂ + 2M → 2MX
• Why is chlorine more reactive than iodine?

  Chlorine has a smaller atomic radius
• What is a halogen displacement reaction?

  A more reactive halogen displaces a less reactive one
• What happens when chlorine reacts with sodium bromide?

  Chlorine displaces bromine
• What color change occurs when chlorine reacts with sodium bromide?

  From colorless to orange-brown
• What is a halide?

  A compound of a Group 7 element and another element
• What is the ionic equation for chlorine displacing bromide?

  Cl₂(aq) + 2Br⁻(aq) → 2Cl⁻(aq) + Br₂(aq)
• Why are noble gases unreactive?

  They have complete outer electron shells
• What is the trend in boiling points for noble gases?

  Boiling points increase down the group
• What is the state of noble gases at room temperature?

  They are all gases
• What happens to the density of noble gases as you go down the group?

  Density increases
• What is the relative atomic mass trend in noble gases?

  It increases down the group
• Why were noble gases previously called inert gases?

  They were thought to not form compounds
• What is the significance of noble gas compounds discovered in the 1960s?

  They showed noble gases can form compounds
• What is the role of weather balloons filled with helium?

  To measure atmospheric conditions