If a gas contains 25 ml of oxygen at 37oC and a pressure of 700 mm Hg, what is the volume under STP.
To find the volume of a gas under Standard Temperature and Pressure (STP), we need to use the ideal gas law equation. The ideal gas law is given as:
PV = nRT
Where:
P = pressure of the gas
V = volume of the gas
n = number of moles of the gas
R = ideal gas constant
T = temperature of the gas in Kelvin
We can rearrange the ideal gas law equation to solve for the volume (V):
V = (nRT) / P
To solve this problem, we need to convert the given temperature from degrees Celsius to Kelvin. The conversion from Celsius to Kelvin is as follows:
T(K) = T(°C) + 273.15
Given:
Temperature (T) = 37°C
Pressure (P) = 700 mm Hg
Volume (V) = 25 ml
First, let's convert the temperature from Celsius to Kelvin:
T(K) = 37°C + 273.15
T(K) = 310.15 K
Now, we can plug the given values into the equation for volume:
V = (nRT) / P
Since we are considering a fixed amount of oxygen, the number of moles (n) can be assumed as 1.
V = (1 * R * 310.15 K) / 700 mm Hg
The ideal gas constant (R) can be approximated as 0.0821 L * atm / (mol * K).
Now, we need to convert the pressure from mm Hg to atm:
1 atm = 760 mm Hg
P(atm) = 700 mm Hg / 760 mm Hg
Finally, we can solve for the volume (V) under STP:
V = (1 * 0.0821 L * atm / (mol * K) * 310.15 K) / (700 mm Hg / 760 mm Hg)
By plugging in these values and performing the calculations, we can determine the volume (V) under STP.