At room temperature oxygen, 
is present in the gas phase.
A gas is defined as a substance which is characterized by the rapidly movement of molecules which are widely separated. The shape and volume of gas is not definite that is they take on the shape of the container in which it is placed. The gas molecules have minimum inter-nuclear attractions and thus have high kinetic energy.
Thus, the sentences that describes oxygen at room temperature are:
- It has no definite volume and takes the shape of its container.
- Its particles move fast enough to overcome the attraction between them.
- It has more energy than it would be at a cooler temperature as the kinetic energy is directly proportional to the temperature that is kinetic energy increases on increasing the temperature.
<h2>Let us complete it :</h2>
Explanation:
let us study about formation of sodium phosphide
Electrons are transferred from atoms of sodium to atoms of phosphorous
The sodium atom looses electrons and the phosphorus atoms
gains electrons .
C. This transfer makes the sodium atoms acquire positive charge and phosphorous acquire negative charge .
As a result, the sodium and phosphorus atoms strongly bond with
each other.
The Lewis structure/diagram for CH2O (aka Formaldehyde) can be written in either of the following ways shown in the picture.
The dots represent electrons in the valence shell of the atom (the outermost shell). The green dots are electrons that belong to the Oxygen atom, the blue belong to the Carbon atom, and the pink belong to the Hydrogen atoms.
Covalent bonds are bonds between atoms where atoms share electrons with each other. Atoms bond because they obey the octet rule ( the rule states that most atoms of main-group elements tend to want 8 electrons in their valence shells).
Oxygen has 6 valence electrons, Carbon has 4, and Hydrogen has 1. H does not follow the octet rule, but C and O do, so the atoms are arranged in this way so that the O and C atoms have a full octet of electrons in their valence.
equation Fe3O4=Fe+CO2 is an impossible reaction
