When a substance is changing state, its temperature remains constant. This is because energy is used to increase/decrease kinetic energy of the molecules of the substance, increasing/decreasing the inter-molecular distance and overcoming the energy bonds present between the molecules. Therefore, no energy is used to raise the temperature of the substance and therefore it remains constant
Answer:

Explanation:
Hello,
Considering the ideal equation of state:

The moles are defined in terms of mass as follows:

Whereas
the gas' molar mass, thus:

Now, since the density is defined as the quotient between the mass and the volume, we get:

Solving for
:

Thus, the result is given by:
![density=\frac{(1atm)(44g/mol)}{[0.082atm*L/(mol*K)]*298.15K} \\density=1.8g/L=1.8x10^{-3}g/mL](https://tex.z-dn.net/?f=density%3D%5Cfrac%7B%281atm%29%2844g%2Fmol%29%7D%7B%5B0.082atm%2AL%2F%28mol%2AK%29%5D%2A298.15K%7D%20%5C%5Cdensity%3D1.8g%2FL%3D1.8x10%5E%7B-3%7Dg%2FmL)
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