To find the mass of helium that will occupy 2 times the volume of 10.0 grams of neon at STP (Standard Temperature and Pressure), we need to use the ideal gas law.
The ideal gas law states that PV = nRT, where P is the pressure, V is the volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature.
At STP, the pressure is 1 atmosphere (atm), the temperature is 273.15 Kelvin (K), and the volume is 22.4 liters (L).
First, we need to calculate the number of moles of neon. We can use the molar mass of neon to convert grams to moles.
Molar mass of neon (Ne) = 20.180 g/mol
Number of moles of neon (n_neon) = mass / molar mass
= 10.0 g / 20.180 g/mol
Next, since we want to find the mass of helium that will occupy 2 times the volume of neon, we need to calculate the volume of neon.
Using the ideal gas law, we can rearrange the equation to solve for V:
V = nRT / P
Substituting the values:
V_neon = (n_neon * R * T) / P
= (n_neon * 0.0821 L·atm/(mol·K) * 273.15 K) / 1 atm
Finally, we can calculate the volume of helium that will occupy 2 times the volume of neon:
V_helium = 2 * V_neon
Now, using the new volume of helium and the same values for P and T, we can find the number of moles of helium (n_helium) using the ideal gas law:
n_helium = (V_helium * P) / (R * T)
To find the mass of helium, we can multiply the number of moles by the molar mass of helium.
Molar mass of helium (He) = 4.0026 g/mol
Mass of helium = n_helium * molar mass of helium
By following this process, you can calculate the mass of helium that will occupy 2 times the volume of 10.0 grams of neon at STP.