1.11 Group 7

• What are the Group 7 elements collectively known as?

  Halogens
• The electron configuration of fluorine is 1s^2 2s^2 2p^5
• Halogens form positive ions (cations) when they gain electrons.

  False
• What is the color of iodine at room temperature?

  Purple
• Fluorine is the most reactive halogen.


  True
• Arrange the halogens in order of decreasing reactivity.

  1️⃣ Fluorine

  2️⃣ Chlorine

  3️⃣ Bromine

  4️⃣ Iodine
• As you go down Group 7, the halogens become less reactive and more dense
• Arrange the halogens in order of increasing atomic size.

  1️⃣ Fluorine

  2️⃣ Chlorine

  3️⃣ Bromine

  4️⃣ Iodine
• The ionization energy of halogens increases as you go down the group
• The Group 7 elements are also known as the halogens
• Arrange the halogens in order of increasing atomic number.

  1️⃣ Fluorine

  2️⃣ Chlorine

  3️⃣ Bromine

  4️⃣ Iodine

  5️⃣ Astatine
• The halogens have low ionization energies and high electronegativity.


  True
• The halogens form negative ions (anions) by gaining one electron
• The halogens form highly reactive covalent bonds due to their high electronegativity and low ionization energies.


  True
• What are two key properties of halogens that contribute to their reactivity?

  High electronegativity and low ionization energies
• Arrange the halogens in order from highest to lowest number of electron shells:

  1️⃣ Astatine

  2️⃣ Iodine

  3️⃣ Bromine

  4️⃣ Chlorine

  5️⃣ Fluorine
• Halogens form covalent bonds with other elements to achieve a stable octet configuration.


  True
• The reactivity of halogens decreases as electronegativity and ionization energy decrease.


  True
• What determines the reactivity of halogens in displacement reactions?

  Reactivity trends
• Bromine can displace iodine from sodium iodide, forming sodium bromide and elemental iodine
• What does the reactivity order of halogens determine in displacement reactions?

  Their ability to displace
• The reactivity of halogens decreases as you go down
• Match the halogen with its reactivity level:

  Fluorine ↔️ Highest

  Chlorine ↔️ High

  Bromine ↔️ Moderate

  Iodine ↔️ Lowest
• The more reactive halogens will always displace the less reactive halogens in displacement reactions.

  True
• Fluorine is used in fluorinated compounds as refrigerants, propellants, and fire retardants
• What is chlorine primarily used for in water treatment?

  Disinfectant
• Match the halogen with one of its key uses:

  Fluorine ↔️ Fire retardants

  Chlorine ↔️ Bleaching agent

  Bromine ↔️ Medicinal drugs

  Iodine ↔️ Nutritional supplement
• Certain halogen compounds can damage the Earth's protective ozone layer
• The halogens become more reactive as you go down the group.

  False
• What type of bonding do halogens form with other elements?

  Covalent
• The reactivity of halogens decreases as you go down the group
• The density of halogens increases as you move down the group.

  True
• The halogens are reactive because they have high electronegativity and low ionization energies
• Match each halogen with its color.

  Fluorine ↔️ Pale yellow

  Chlorine ↔️ Greenish-yellow

  Bromine ↔️ Reddish-brown

  Iodine ↔️ Purple
• The electronegativity of halogens increases as you move down Group 7.

  False
• Match each halogen with its number of electron shells.

  Fluorine ↔️ 2

  Chlorine ↔️ 3

  Bromine ↔️ 4

  Iodine ↔️ 5
• The halogens become less reactive as their atomic size increases.


  True
• Halogens readily form negative ions, also known as anions
• The halogen with the highest reactivity is fluorine
• Arrange the halogens in order from lowest to highest melting/boiling points:

  1️⃣ Fluorine

  2️⃣ Chlorine

  3️⃣ Bromine

  4️⃣ Iodine