I just want to make sure that D is the correct answer.
Each halogen is a diatomic element. However, under normal conditions chlorine is a gas, bromine is a liquid, and iodine is a solid. What is the best explanation for this difference?
A. The strength of the covalent bond between atoms increases from chlorine to bromine to iodine.
B. The strength of the intramolecular forces increases from chlorine to bromine to iodine.
C. The strength of the dipole-induced dipole attractions between atoms increases from chlorine to bromine to iodine.
D. The strength of the London dispersion forces between molecules increases from chlorine to bromine to iodine.
Yes, D.
It's D I promise I took the quiz
To determine the best explanation for the observed difference in physical states of chlorine, bromine, and iodine under normal conditions, let's evaluate each option step-by-step:
A. The strength of the covalent bond between atoms increases from chlorine to bromine to iodine.
- This option implies that the difference in physical states is due to the increased strength of the covalent bond between the atoms of each halogen.
- However, the physical state of a substance is primarily determined by the intermolecular forces between molecules, rather than the strength of the covalent bond within the molecule.
- Therefore, option A is not the best explanation for the observed difference.
B. The strength of the intramolecular forces increases from chlorine to bromine to iodine.
- This option suggests that the difference is due to the increased strength of intramolecular forces within each halogen.
- However, intramolecular forces refer to the interactions between atoms within a molecule, whereas the question asks about the physical state differences between halogens.
- Therefore, option B is not the best explanation.
C. The strength of the dipole-induced dipole attractions between atoms increases from chlorine to bromine to iodine.
- Dipole-induced dipole attractions occur between polar molecules, which have a permanent dipole.
- Since the question mentions that halogens are diatomic elements, there is no permanent dipole present.
- Therefore, option C is not the best explanation.
D. The strength of the London dispersion forces between molecules increases from chlorine to bromine to iodine.
- London dispersion forces, or van der Waals forces, occur between all molecules, regardless of polarity.
- These forces are caused by temporary fluctuations in electron distribution, resulting in temporary dipoles.
- Larger and more massive molecules experience stronger London dispersion forces.
- Iodine has the largest number of electrons and is the most massive halogen, which leads to stronger London dispersion forces between iodine molecules.
- This difference in London dispersion forces can explain why iodine is a solid, while chlorine is a gas and bromine is a liquid under normal conditions.
- Therefore, option D is the best explanation for the observed difference.
In conclusion, the best explanation for the difference in physical states of chlorine, bromine, and iodine is that the strength of the London dispersion forces between molecules increases from chlorine to bromine to iodine, making option D the correct answer.
To determine the correct answer, let's go through each option and see how we can evaluate them.
A. The strength of the covalent bond between atoms increases from chlorine to bromine to iodine.
This option suggests that the strength of the covalent bond between the halogen atoms increases from chlorine to bromine to iodine. However, this is not the best explanation for the difference in their states at normal conditions (gas, liquid, or solid), as the covalent bonds within the halogen molecules remain relatively similar.
B. The strength of the intramolecular forces increases from chlorine to bromine to iodine.
Intramolecular forces refer to the forces within a molecule. The question is asking about the states of halogens under normal conditions, which are determined by intermolecular forces between molecules, rather than intramolecular forces. Therefore, this option is not the best explanation.
C. The strength of the dipole-induced dipole attractions between atoms increases from chlorine to bromine to iodine.
Dipole-induced dipole attractions occur when there is a temporary imbalance of electron distribution in a molecule. While these forces may contribute to the intermolecular forces between halogens, they are not the most significant factor in determining their states. Hence, this option is not the best explanation.
D. The strength of the London dispersion forces between molecules increases from chlorine to bromine to iodine.
London dispersion forces (also known as van der Waals forces) are temporary attractions between molecules caused by the fluctuation of electron distribution. These forces increase with the size and number of electrons in the atoms or molecules involved. In this case, chlorine has the fewest electrons, bromine has more, and iodine has the most, making the London dispersion forces stronger as we move from chlorine to bromine to iodine. Therefore, D is the best explanation for the difference in the states of the halogens.
In conclusion, the correct answer is D. The strength of the London dispersion forces between molecules increases from chlorine to bromine to iodine.