STP condition mean we have P=1 atm. T=273K. R=ideal gas constant, but make sure you use the one that has the same units of pressure, temperature that you are using. In this case R=0.0821 L*atm K^-1mol^1. You are provided with n=2.1 moles.
V=nRTP
Input your values and solve.
Every organic molecules/compound contains carbon (c).
Some other very abundant are hydrogen, nitrogen, oxygen, phosphorus, and sulfur.
I learned this with the acronym CHNOPS.
C - Carbon
H - Hydrogen
N - Nitrogen
O - Oxygen
P - Phosphorus
S - Sulfur
Hope this helps!
The answer is C. because <span>particles settle out over time ,can block light and scatter light .</span>
Use pv=nrT
where p is the pressure,
v is the volume,
n is the number of mole (which can be equal to mass /mr),
T is the temperature in kelvin,
and r is (molar constant) = 8.31 (units)