We have to know the number of Na⁺ ions in the unit cell.
The number of Na⁺ ions in the unit cell is (D) 8.
Sodium oxide (Na2O) crystallizes in a structure in which the O2– ions are in a face - centered cubic lattice and the Na+ ions are in tetrahedral holes.
O²⁻ ions are in a face centred cubic lattice, so the number of O²⁻ ions per unit cell is equal to 4. The number of tetrahedral hole= 2 X 4=8. Na+ ions are present in tetrahedral holes, which indicates there are 8 number of Na+ ions in the unit cell.
Answer:
O FX will be greater than FY
Explanation:
<em>Surface tension</em> can be defined as the force required to stretch one film of a given fase (usually with liquids).
This required force is proportional to the liquid's surface tension. This means that the higher the surface tension, the higher the required force to stretch it is.
Functional groups create reactive sites in molecules.
The polar part of a molecule that can hydrogen bond to water is said be hydrophilic.
Pi (π) bonds create active sites and will react with electron-deficient species.
A electronegative heteroatom like nitrogen, oxygen, or a halogen makes a carbon atom electrophilic.
(carbon will have less electronic density, which is attracted by the more electronegative heretoatoms, and it will tend to attract electron rich chemical species, and in this situation we say that the carbon atom is electrophilic).
The nonpolar part of a molecule that is not attracted to water is said to be hydrophobic.
A lone pair on a heteroatom makes it basic and nucleophilic.
(the heteroatom with the lone pair will tend to attract electron poor chemical species, and in this situation we say that the heteroatom is nucleophilic).
Answer:
4. The combined volume of the Ar atoms is too large to be negligible compared with the total volume of the container.
Explanation:
Deviations from ideality are due to intermolecular forces and to the nonzero volume of the molecules themselves. At infinite volume, the volume of the molecules themselves is negligible compared with the infinite volume the gas occupies.
However, the volume occupied by the gas molecules must be taken into account. Each <u>molecule does occupy a finite, although small, intrinsic volume.</u>
The non-zero volume of the molecules implies that instead of moving in a given volume V they are limited to doing so in a smaller volume. Thus, the molecules will be closer to each other and repulsive forces will dominate, resulting in greater pressure than the one calculated with the ideal gas law, that means, without considering the volume occupied by the molecules.
