Question

Elements X and Y are in group VII of the periodic table, X is a liquid, while Y is a solid at room temperature. Which statement is correct?
1.Atoms of Y have more protons than atoms of X.
2.Molecules of Y have more atoms than molecules of X.
3.Y displaces X from an aqueous solution of X- ions.
A.1
B.2
C.3
D.All of them

Answer 1

We know that there are three states of a matter: solid, liquid and gas. Solids have their own shape and volume. They have highly ordered structures. Liquids occupy the shape of the container but they have definite volume. Gases are free to move anywhere. They have low density and high compressibility.

Complete step by step answer:
-We must remember that the elements present in group 7 of the periodic table are fluorine, chlorine, bromine, iodine, and astatine. This family is also called the halogen family. In their elemental form, the halogens form diatomic molecules linked by single bonds.
-The diatomic molecules of halogens are nonpolar, the interactions are weak London forces as the atom size increases, melting and boiling points increase. London forces turn stronger, and thus boiling and melting points increase.
-We know in the periodic table, the melting point of a solution decreases down the group. Also, the atomic number (or) protons increases on moving down the group. So atoms of Y could contain more protons when compared to the atoms of X.
Therefore, the option (A) is correct.

Note:
We must know that in solids, the intermolecular forces are stronger since the particles are tightly packed with each other. In liquids, the intermolecular forces are not strong enough to keep the molecules from moving particles, hence liquids hold the shape of the container. In case of gases the intermolecular forces are very weak, and the weak intermolecular force permits gases to expand. The types of attractive forces/intermolecular forces are,
1.Dipole-Dipole forces
2.Induced-dipole forces
3.Hydrogen bonding
4.London dispersion forces