Respuesta :
Answer:
The answer to your question is 8.74 g of He
Explanation:
Data
V = 2.4 x 10² L
P = 99 kPa
T = 0°C
mass = ?
Process
1.- Convert kPa to atm
P = 99 kPa = 99000 Pa
1 atm --------------- 101325 Pa
x --------------- 99000 Pa
x = (99000 x 1) / 101325
x = 0.977 atm
2.- Convert temperature to °K
°K = 273 + 0
°K = 273
3.- Substitution
PV = nRT
- Solve for n
n = PV / RT
n = (0.977)(2.4 x 10²) / (0.082)(273)
n = 24.48 / 22.386
n = 1.093 moles
4.- Calculate the grams of He
8 g -------------------- 1 mol
x -------------------- 1.093 moles
x = (1.093 x 8) / 1
x = 8.74 g
Answer:
The mass of the helium gas is 42 grams
Explanation:
Step 1: Data given
Volume of the balloon = 2.4 *10^2 L = 240 L
Temperature = 0°C = 273 K
Pressure = 99 kPa = 0.977054 atm
Molar mass He2 = 4.0 g/mol
Step 2: Calculate moles He
p*V = n*R*T
⇒with p = the pressure = 0.977054 atm
⇒with V = the volume = 240 L
⇒with n = the number of moles = TO BE DETERMINED
⇒with R = the gas constant = 0.08206 L*atm/mol*K
⇒with T = the temperature = 273 K
n = (p*V) / (R*T)
n = (0.977054 * 240 ) / (0.08206 * 273)
n = 10.467 moles
Step 3: Calculate mass of Helium
Mass He = Moles He * molar mass He
Mass He = 10.467 moles * 4.0 g/mol
Mass He = 42 grams
The mass of the helium gas is 42 grams
NOTE: The noble gases (helium, neon, argon, krypton, xenon, and radon) are gases at STP and are monatomic
