Groups, states of matter, nanoparticules

• What are Group 1 elements commonly known as?

  Alkali metals
• Why are Group 1 elements considered reactive?

  They have one electron in their outer shell, making them very reactive.
• List the alkali metals in Group 1.

  Lithium, sodium, potassium, rubidium, caesium, and francium.
• What trend occurs in reactivity as you go down Group 1?

  Reactivity increases as you go down the group.
• Explain why the outer electron of alkali metals is more easily lost as you go down the group.

  The attraction between the nucleus and the outer electron decreases because the electron is further away from the nucleus.
• What physical properties do alkali metals share?

  They are all soft and have low density.
• What are the trends for alkali metals as you go down Group 1?

  • Increasing reactivity
  • Lower melting and boiling points
  • Higher relative atomic mass
• How do alkali metals form ions?

  They readily lose their one outer electron to form 1+ ions.
• What type of compounds do alkali metals form with non-metals?

  They form ionic compounds.
• What happens when Group 1 metals react with water?

  They react vigorously to produce hydrogen gas and metal hydroxides.
• How does the reactivity of alkali metals with water change down the group?

  The more reactive the alkali metal, the more violent the reaction with water.
• What is produced when potassium reacts with water?

  Hydrogen gas and potassium hydroxide.
• What do Group 1 metals form when they react with chlorine?

  They form white metal chloride salts.
• How does the reactivity of alkali metals with chlorine change down the group?

  Reactivity increases, making the reaction more vigorous.
• What type of oxide does lithium form when it reacts with oxygen?

  Lithium oxide (Li₂O).
• What type of oxide does sodium form when it reacts with oxygen?

  A mixture of sodium oxide (Na₂O) and sodium peroxide (Na₂O₂).
• How do Group 1 metals compare to transition metals in terms of reactivity?

  Group 1 metals are much more reactive than transition metals.
• What is a characteristic of the density and strength of Group 1 metals compared to transition metals?

  Group 1 metals are much less dense, strong, and hard than transition metals.
• What are Group 7 elements commonly known as?

  Halogens
• What is the state of fluorine at room temperature?

  It is a very reactive, poisonous, pale yellow gas.
• Describe the physical state of chlorine at room temperature.

  Chlorine is a fairly reactive, poisonous, pale green gas.
• What is the physical state of bromine at room temperature?

  Bromine is a dense, poisonous, red-brown, volatile liquid.
• What is the physical state of iodine at room temperature?

  Iodine is a dark grey crystalline solid or a purple vapour.
• What do all Group 7 elements have in common regarding their outer shell?

  They all have seven electrons in their outer shell.
• What are the trends for halogens as you go down Group 7?

  • Become less reactive
  • Higher melting and boiling points
  • Higher relative atomic masses
• How do halogens form molecular compounds?

  They share electrons via covalent bonding with other non-metals.
• What ions do halogens form when they bond with metals?

  They form 1- ions called halides.
• What is an example of a halide compound?

  Sodium chloride (NaCl).
• What happens in a displacement reaction involving halogens?

  A more reactive halogen can displace a less reactive one from its salt.
• Predict whether bromine would displace iodine from sodium iodide and explain why.

  Bromine would not displace iodine because it is less reactive than iodine.
• What are Group 0 elements commonly known as?

  Noble gases
• What is a characteristic of noble gases regarding their reactivity?

  Noble gases are inert and do not react at room temperature.
• How many electrons do noble gases have in their outer energy level?

  They all have eight electrons in their outer energy level.
• What happens to the boiling points of noble gases as you move down the group?

  The boiling points increase as you move down the group.
• Why does the boiling point of noble gases increase down the group?

  It is due to an increase in the number of electrons leading to greater intermolecular forces.
• If neon is a gas at 25 °C, what state is helium at this temperature?

  Helium is also a gas at 25 °C.
• What are the states of matter and their characteristics?

  • Solid: Fixed shape and volume, strong forces of attraction.
  • Liquid: Definite volume, no definite shape, weak forces of attraction.
  • Gas: No definite shape or volume, very weak forces of attraction.
• What does particle theory explain about solids?

  Particles are held close together in fixed positions, forming a regular lattice arrangement.
• How do particles behave in liquids?

  Particles are free to move past each other but tend to stick close together.
• What is the behavior of particles in gases?

  Particles move constantly with random motion and are far apart.