Each isotope of Oxygen has a different number of neutrons
<h3>Further explanation
</h3>
The elements in nature have several types of isotopes
Atomic mass is the average atomic mass of all its isotopes
Isotopes are atoms has the same number of protons but has a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Some of the isotopes of oxygen are:

Each isotope has 8 protons and 8 electrons but has a different number of neutrons
For O-16: number of neutrons = 16-8 = 8
For O-17: number of neutrons = 17-8 = 9
For O-18: number of neutrons = 18-8 = 10
Answer:
2.44 K IS THE TEMPERATURE OF THE GAS
Explanation:
PV = nRT
P = 0.5 atm
V = 2 L
n = 5 moles
R = 0.082 L atm mol^-1 K^-1
T = ?
Substituting for T in the equation, we obtain:
T = P V / nR
T = 0.5 * 2 / 5 * 0.082
T = 1 / 0.41
T = 2.44 K
The temperature of the gas is 2.44 K
C
explanation; ( i’m smart )
At room temperature, O2 is in gaseous state.
a gas has no definite volume or definite shape. It occupies volume of container and attains shape of container only.
Thus
It has no definite volume and takes the shape of its container.
Its particles move fast enough to overcome the attraction between them.: the gas molecules have minimum intermolecular interactions and have high kinetic energy.
It has more energy than it would at a cooler temperature: the kinetic energy of gas molecules increases with increase in temperature. Thus the energy increases with temperature and decreases with decrease in temperature.