<span>STP means standard temperature
and pressure at 0°C (273K) and 1 atm (atmosphere). The density of the unknown
gas is 0.63 gram per liter. The deal gas equation is PV = nRT. The n is the
numer of moles and can be represented as mass of the gas, m, divided by the
molar mass, c. so we have,</span>
PV = nRT
PV = (m/c)RT
Since the density is d = m/V
Pc = (m/V)RT
Pc = dRT
c = drT/P
substitute the values into the equation,
c = [(0.63g/L)(0.08206
L-atm/mol-K)(273K)]/(1atm)
<u>c = 14.11 g/mol</u>
<h2>Hello!</h2>
The answer is: 4.77atm
<h2>Why?</h2>
Since there's a fixed volume, we can use the the Gay-Lussac's Law which stablish a relation between the pressure and the temperature:

<em>P</em> is the volume of the gas
<em>t</em> is the temperature of the gas
<em>k </em>is the proportionality constant
We also have the following equation:

Where:

We are asked to find the pressure in atm, so we must convert 483.73kPa to atm:

Then,

Have a nice day!
True.
Every environment and ecosystem will include these factors.