Question

Based on the three formulas shown, use one of them to solve for the purple yellow and red box and explain how you did it.

Answer 1

P = 11.133 atm (purple)

T = -236.733 °C(yellow)

n = 0.174 mol(red)

Further explanation  

Some of the laws regarding gas, can apply to ideal gas (volume expansion does not occur when the gas is heated),:  

• Boyle's law at constant T, P = 1 / V  
• Charles's law, at constant P, V = T  
• Avogadro's law, at constant P and T, V = n  

So that the three laws can be combined into a single gas equation, the ideal gas equation  

In general, the gas equation can be written  

$\large {\boxed {\bold {PV = nRT}}}$

where  

P = pressure, atm  

V = volume, liter  

n = number of moles  

R = gas constant = 0.08206 L.atm / mol K  

T = temperature, Kelvin  

To choose the formula used, we refer to the data provided

Because the data provided are temperature, pressure, volume and moles, than we use the formula PV = nRT

• Purple box

T= 10 +273.15 = 373.15 K

V=5.5 L

n=2 mol

$\tt P=\dfrac{nRT}{V}\\\\P=\dfrac{2\times 0.08205\times 373.15}{5.5}\\\\P=11.133~atm$

• Yellow box

V=8.3 L

P=1.8 atm

n=5 mol

$\tt T=\dfrac{PV}{nR}\\\\T=\dfrac{1.8\times 8.3}{5\times 0.08205}\\\\T=36.42~K=-236.733^oC$

• Red box

T = 12 + 273.15 = 285.15 K

V=3.4 L

P=1.2 atm

$\tt n=\dfrac{PV}{RT}\\\\n=\dfrac{1.2\times 3.4}{0.08205\times 285.15}\\\\n=0.174~mol$