<span>STP means standard temperature
and pressure at 0°C (273K) and 1 atm (atmosphere). The density of the unknown
gas is 0.63 gram per liter. The deal gas equation is PV = nRT. The n is the
numer of moles and can be represented as mass of the gas, m, divided by the
molar mass, c. so we have,</span>
PV = nRT
PV = (m/c)RT
Since the density is d = m/V
Pc = (m/V)RT
Pc = dRT
c = drT/P
substitute the values into the equation,
c = [(0.63g/L)(0.08206
L-atm/mol-K)(273K)]/(1atm)
<u>c = 14.11 g/mol</u>
<span>A fizz saver forms an airtight seal around the now-upsidedown soda bottle, and the pressure exerted by the drink and the atmospere outside pushes out the drink through the slightly-elevated spout. The CO2 gas does not fizz out because it stays at the bottom of the upside-down bottle. Thus the CO2 gas is trapped and the drink is carbonated at a longer time.</span>
J.J Thompson’s model shows a sphere with electrons that are moving around freely. However, Thompson’s model does not show protons or neutrons. The model that we have today gives a clearer structure showing protons, neutrons, and electrons inside an atom.
