T2 HALOGENS Flashcards
What is the electronic configuration of the halogens?
The electronic configuration is ns² np⁵.
What type of ions do halogens form?
They form very stable mononegative ions.
How are halogens found in their elemental state?
They form diatomic molecules by sharing the unpaired electron.
What is the standout property of halogens in terms of reactivity?
They have a strong oxidizing power.
What happens to the ionization energies of halogens as they move from left to right in the group?
They increase due to the increase in effective nuclear charge.
What is the most electronegative element in the periodic table?
Fluorine (F) is the most electronegative.
Why do halogens exhibit different colors?
Due to a shift in light absorption towards higher wavelengths.
What effect does atomic size have on the dissociation energy of halogens?
It decreases down the group, except for F2 due to interelectronic repulsions.
What color of light is absorbed by iodine?
Yellow.
How does the electron affinity of halogens vary as they descend in the group?
It increases, except for fluorine due to interelectronic repulsions.
Which element has the highest electron affinity in the group?
Fluorine.
What happens to the free energy of hydration as you go up the group?
It decreases due to the lower charge density of large anions.
How does the redox potential of halogens change?
It decreases and has a very high and anomalous value for fluorine.
What is the best oxidant in the halogen group?
F2.
What is the best reductant in the halogen group?
I-.
In which medium is the oxidizing power higher: acidic or basic?
It is always higher in acidic medium.
How it increase size in halogens?
Down
How it increase ionization energy in halogens?
up
How it increase electronegativity in halogens?
up
How it increase the bond. MP and BP in halogens?
down
Why is fluorine considered a “superhalogen”?
Due to its small size, which makes it highly reactive and electronegative.
Which elements does fluorine not react with?
It does not react with helium (He) or neon (Ne).
What compounds can’t F2 extract?
It cannot extract H2 except in the case of HF.
How does F2 react with metals?
It forms fluorides with all metals; however, some, such as Cu, Ni, Al, and Fe, passivate due to the formation of MF2.
What type of bond does fluorine form with the greatest strength?
It forms the strongest hydrogen bonds due to its high electronegativity.
Why is the F-F bond weaker than expected?
The non-bonding electronic repulsion of the F atoms in the molecule due to their small size.
What is the difference in the oxidizing power of F2 compared to other halogens?
The oxidizing power of F2 is much greater due to the weakness of the F-F bond and the higher hydration energy of the F- anion.
What causes fluorides to have higher lattice energy (U) compared to other halides?
The small size of the F- anion.
Why does fluorine form the strongest covalent bonds?
Due to its small size, which allows for better orbital overlap, and its high electronegativity.
What is the main difference in the solubility of fluorides compared to other halides?
Fluorides have different solubility due to their ionic nature, bond limitations of fluorine, and low polarizability.
How is fluorine (F2) obtained, and what is its abundance in Earth’s crust?
Fluorine is obtained from fluorite (CaF2), and it’s the 13th most abundant element in Earth’s crust.
Why is obtaining F2 in aqueous solution impossible, and how is F2 obtained through electrolysis?
F2 oxidizes H2O to O2, making aqueous production impossible. It’s obtained via electrolysis of HF(g) dissolved in molten KF.
How is chlorine (Cl2) currently obtained and what are the key methods used in industry?
Cl2 is obtained from seawater’s NaCl through electrolysis. Different methods include the mercury cell, diaphragm cell, and Downs cell.
Explain the three electrolytic setups used in chlorine production.
The setups include the mercury cell, diaphragm cell, and Downs cell, differing in how they separate the anode and cathode.