A certain mass of calcium carbide, CaC2, reacts completely with water to produce 64.5 L of acetylene, C2H2, at 50 degrees C and 1 atm. If the same reactants react completely at 300 degrees C and 1 atm, what will be the volume of acetylene?
Solution This solution is FREE courtesy of BrainMass!
First, we have to realize that the pressure is unchanged, thus the volume and the temperature are the only variables. The gas law, which is derived for constant pressure and shows the relationship between volume and temperature, is Charles's Law: V1/T1 = V2/T2, meaning that V1 is directly proportional to T1 and V2 is directly proportional to T2.
(The assumption we make here is that the acetylene gas is an ideal gas.)
So we can write the equation:
V2 = V1xT2/T1 = 64.5x573.15/323.15 = 114.4 L
Note that the temperatures should be in Kelvin in order to be able to use them in the gas laws! (Therefore 273.15 was added to the degrees Celsius values.)