consider the following container of helium at 45C. intially the valve is closed. After the valve is opened what is the pressure of the helium gas.
your start points are 2.00 atm and 9.00L.
after opening you have 3.oo atm and 3.00L.
The answer is 2.25 atm
what formula did you use to come to this conclusion.
Please help I missed a few days and I'm confused.
To determine the pressure of the helium gas after opening the valve, you can use the ideal gas law equation:
PV = nRT
where:
P = pressure (in atm)
V = volume (in L)
n = number of moles
R = ideal gas constant (0.0821 L·atm/(mol·K))
T = temperature (in Kelvin)
First, we need to convert the initial and final temperatures from Celsius to Kelvin:
Initial temperature (T1) = 45°C + 273.15 = 318.15 K
Final temperature (T2) = ? (not given)
Since the valve is closed initially, the number of moles (n) and the pressure (P1) are constant. Therefore, we can rewrite the ideal gas law equation as:
P1V1 = P2V2
Rearranging the equation to solve for the final pressure (P2), we have:
P2 = (P1V1) / V2
Given:
P1 = 2.00 atm
V1 = 9.00 L
V2 = 3.00 L
Substituting the values into the equation:
P2 = (2.00 atm * 9.00 L) / 3.00 L
P2 = 18.00 atm·L / 3.00 L
P2 = 6.00 atm
Therefore, the pressure of the helium gas after opening the valve is 6.00 atm. This contradicts the provided answer of 3.00 atm, so please double-check the values given in the question.
To determine the pressure of the helium gas after the valve is opened, you can use the combined gas law equation, which relates the initial and final conditions of a gas sample. The combined gas law equation is given by:
(P₁ * V₁) / T₁ = (P₂ * V₂) / T₂
Where:
P₁ and P₂ are the initial and final pressures of the gas, respectively.
V₁ and V₂ are the initial and final volumes of the gas, respectively.
T₁ and T₂ are the initial and final temperatures of the gas, respectively.
In this case, you are given the initial and final pressures (P₁ = 2.00 atm, P₂ = 3.00 atm), and the initial and final volumes (V₁ = 9.00L, V₂ = 3.00L). However, you are not given the temperature.
In order to use the combined gas law equation, you need to convert the temperatures to absolute temperature scales, such as Kelvin. The temperature can be converted using the formula:
T(K) = T(°C) + 273.15
For example, if the temperature is given as 45°C, you would convert it to Kelvin as follows:
T(K) = 45 + 273.15 = 318.15 K
Now that you have the initial and final temperatures (T₁ and T₂), as well as the initial and final pressures (P₁ and P₂), you can use the combined gas law equation to find the missing variable, which in this case is the final pressure (P₂). Rearrange the equation to solve for P₂:
P₂ = (P₁ * V₁ * T₂) / (V₂ * T₁)
Let's substitute the given values into the equation:
P₂ = (2.00 * 9.00 * T₂) / (3.00 * T₁)
Since the initial and final temperatures are not provided, we cannot calculate the exact pressure. Therefore, it is not possible to determine the pressure of the helium gas after the valve is opened with the given information.