AQA Chemistry A Level Group 7

Why does the boiling point of Group 7 elements increase down the group?

• increased number of electrons in larger atoms, the van der waals forces between atoms increase so less energy is required to separate the molecule

• increased number of electrons in larger atoms, the van der waals forces between molecules increase so more energy is required to separate the molecule

• The boiling point increases down the group due to weaker intermolecular forces

• The boiling point increases down the group due to smaller atomic size

Why does the atomic radius of the Group 7 elements increase down the group?

• The atomic number decreases down the group, leading to a smaller atomic radius
• The electrons are pulled closer to the nucleus due to increased shielding effects
• The greater the atomic number, the more electrons there are, which go into shells increasingly closer to the nucleus.

• There is an increasing number of shells so more shielding and less pull on the outer electrons and an increasing atomic radius so attraction of nucleus for outer electrons drops off as distance increases

Why does the electronegativity of the Group 7 elements decrease down the group?

• The electronegativity decreases due to the increase in ionization energy
• The electronegativity decreases due to the increase in electron affinity
• The electronegativity decreases due to the increase in metallic character
• There is an increasing number of shells so more shielding and less pull on the outer electrons and an increasing atomic radius so attraction of nucleus for outer electrons drops off as distance increases

What is the trend in oxidising power of Group 7 elements down the group?

• It increases

• H2SO4 + 6 H+ + 6 I- → 3 I2 + S + 4 H2O
• Chlorine changes from 0 to -1 and 0 to +1 in the same reaction.
• It decreases

Why does the oxidising power of Group 7 elements decrease down the group?

• the increasing nuclear charge which should attract electrons more is offset by DECREASED SHIELDING and DECREASING ATOMIC RADIUS

• the increasing nuclear charge which should attract electrons more is offset by INCREASED SHIELDING and DECREASING ATOMIC RADIUS

• the increasing nuclear charge which should attract electrons more is offset by INCREASED SHIELDING and INCREASING ATOMIC RADIUS
• the increasing nuclear charge which should attract electrons more is offset by DESCREASED SHIELDING and INCREASING ATOMIC RADIUS

Write a balanced chemical equation with state symbols for the reaction of Chlorine with Sodium Bromide

• 2NaBr + Cl2 -> NaCl + Br2
• 2NaBr + Cl2 -> 2NaCl + 2Br
• Cl2(aq) + 2NaBr(aq) ——> Br2(aq) + 2NaCl(aq)

• NaBr + Cl2 -> NaCl + Br

Write an balanced ionic equation for the reaction of bromine with iodide ions

• Br₂ + 2I¯ ——> I₂ + 2Br¯

• Br₂ + I^- -> Br- + I₂

• Br₂ + 2I^- -> 2Br- + I₂

• 2Br₂ + I^- -> Br- + I₂

What observation would be made with bromine is reacted with sodium chloride?

• No visible reaction.
• Solution goes from colourless to orange-red

• Solution goes from colourless to brown

• Solution goes from colourless to purple

What observation would be made with chlorine is reacted with sodium iodide?

• Solution goes from colourless to brown

• A green gas is released.
• A white precipitate of sodium iodide is formed.
• A red solution is produced.

What observation would be made when solid sodium chloride reacts with concentrated sulfuric acid?

• Oxygen gas is evolved
• green chlorine gas is evolved

• Solution goes from colourless to orange-red

• steamy fumes of hydrogen chloride gas is evolved