Question

Determine which law is appropriate for solving the following problem. What volume will 1.56 liters of a gas at 27°C and 745 mmHg of pressure occupy at 100°C and 700 mmHg of pressure? Law used:

Answer 1

Answer: To determine the final Volumen of the gas we use the Combined gas law

Step-by-step explanation:

The combined gas law combines three gas laws: Boyle's Law, Charles' Law, and Gay-Lussac's Law, this law links pressure, volume, and temperature of a giving gas, from initial conditions ( expressed with the number 1) to final conditions (expressed with the number 2)

P1V1 / T1 = P2V2 / T2

• In our exercise, we state the initial conditions of the gas, ( keep in mind that this law works only with absolute temperatures, then we need to convert degrees Celsius to the Kelvin scale)

P1 = 745 mm Hg

V1 = 1,56 L

T1 = 27°C + 273,17K = 300.15 K

• Now we state the final conditions and the parameter we need to calculate

P2 = 700 mm Hg

V2 = x (the unknown you're solving for)

T2 = 100°C + 273,15K = 373.15 K

• Finally, we take the formula and we isolate the V2 that we are interested in and fill in the rest with the information giving.

V2 = (P1 V1 T2) / (P2 T1)

V2= (745 mm Hg . 1,56 L . 373.15 K) / ( 700 mm Hg . 300.15 K )

V2 = 2,06 L

Answer 2

We use the general gas law or the combined gas law to solve this kind of problem

Step-by-step explanation:

The general gas law is a combination of both Boyle's law and Charle's law. It is expressed as:

`( P₁V₁)/(T₁)` =
`( P₂V₂)/(T₂)`

The unkown is V₂ which can be derived by substituting in the equation above.

The general gas law assumes that, n, the number of mole is 1