In: Chemistry
You have several identical balloons. You experimentally determine that a balloon will break if its volume exceeds 0.820 L. The pressure of the gas inside the balloon equals air pressure (1.00 atm).
(a) If the air inside the balloon is at a constant temperature of 21.8
(a) PV = nRT...(1)
P = 1 atm, V = 0.820 L, T = 21.8 + 273 = 294.8 K, R = 0.082 L?atm?K?1?mol?1,
Molecular mass of air is calculated as follows:
Nitrogen (N2) (78.084%)
Oxygen (O2) (20.946%)
Argon (Ar) (0.9340%)
Carbon dioxide (0.0387%)
Neon (Ne) (0.001818%)
Helium (He) (0.000524%)
Methane (CH4) (0.000179%)
Krypton (Kr) (0.000114%)
& there is more
then add up those %'s of their molar masses:
Nitrogen (N2) (78.084% of 28.0134 g/mol = 21.8740
Oxygen (O2) (20.946%of 31.9989 g/mol = 6.7025
Argon (Ar) (0.9340% of 39.9481 g/mol= 0.3731
Carbon dioxide (0.0387% of 44.0096 g/mol = 0.0170
& so far you get 28.967 g/mol
Substitute all values in equation 1
1 * 0.820 = (w / 28.967) * 0.082 * 294.8
0.820 * 28.967 = w * 241.73
23.75 / 241.73 = w
w = 0.09 g
(b) If helium is there then Molecular mass = 4.0 g
1 * 0.820 = (w / 4.0 ) * 0.082 * 294.8
0.820 * 4.0 = w * 241.73
3.28 / 241.73 = w
w = 0.01 g