Reactions and Properties of Halogens

This set of flashcards covers key concepts related to the properties, reactions, and trends of halogens as presented in the lecture notes.

What trend is observed in atomic radius as you move down Group 7 (halogens)?

Atomic radius increases as more electron shells are added.

What happens to the boiling points of halogens as you move down the group?

Boiling points increase due to increased atomic radius and stronger London dispersion forces.

How does electronegativity change as you go down Group 7?

Electronegativity decreases because outermost electrons are further from the nucleus.

What is the state and color of chlorine (Cl2) at room temperature?

Chlorine is a green gas.

What color is bromine (Br2) and what is its state at room temperature?

Bromine is a red/brown liquid.

How does the oxidizing ability of halogens change down the group?

The oxidizing ability decreases due to increased atomic radius and shielding.

What will happen in a displacement reaction involving Cl2 and Br−?

Cl2 will displace Br− as it is a stronger oxidizing agent.

What is the ionic equation for the reaction of Cl2 with KBr?

Cl2(aq) + 2 Br−(aq) → 2 Cl−(aq) + Br2(aq).

What type of reaction occurs when chlorine reacts with water?

Chlorine undergoes a disproportionation reaction.

What products are formed when chlorine reacts with water in the presence of sunlight?

Chloride ions (Cl−) and oxygen (O2) are produced.

How do hydrogen halides react with water?

They produce an acidic solution as they are proton donors.

What is the overall reaction when NaI reacts with concentrated H2SO4?

8 NaI(s) + 5 H2SO4(l) → 4 Na2SO4(s) + 4 I2(s/g) + H2S(g) + 4 H2O(l).

What color precipitate does silver chloride (AgCl) form?

A white precipitate is formed.

How does the reducing ability of halides change down the group?

The reducing ability increases due to larger ionic radii and easier removal of outer electrons.

What is formed when Br− reacts with concentrated H2SO4?

A colorless acidic gas (SO2) and a red-brown liquid (Br2) are produced.

What observations can be made when I− reacts with concentrated H2SO4?

White steamy fumes of HI, dark grey solid (I2), and a rotten egg smelling gas (H2S) are produced.