Question 1

Elements in group 17 share poor thermal conductivity and poor electrical conductivity.

Elements in group 17, also known as the halogens, are characterized by poor thermal conductivity and poor electrical conductivity due to their molecular structure and the nature of their bonding.

A) Poor thermal conductivity

This option is correct because halogens exist as diatomic molecules and do not allow free movement of electrons, which results in low thermal conductivity. Their molecular bonds do not facilitate the transfer of heat effectively, distinguishing them from metals, which are known for high thermal conductivity.

B) Good thermal conductivity

This option is incorrect. Halogens do not exhibit good thermal conductivity as their molecular structure does not support the efficient transfer of thermal energy. Unlike metals, the bonding in halogens limits their ability to conduct heat well.

C) Good electrical conductivity

This option is incorrect. Halogens are generally poor electrical conductors because they do not have free-flowing electrons like metals do. Their diatomic molecular structure impedes the movement of charge, resulting in low electrical conductivity.

D) Poor electrical conductivity

This option is correct as halogens typically do not conduct electricity well. Their lack of free electrons and the presence of covalent bonds contribute to their poor electrical conductivity, making them unsuitable for applications requiring conductive materials.

Conclusion

In summary, elements in group 17 share the properties of poor thermal conductivity and poor electrical conductivity, which stem from their molecular nature and bonding characteristics. The other options fail to represent the conductive properties of halogens, affirming A and D as the correct choices.