A neon light sign is advertising for a clothing shop on the beach. The neon gas sign is at STP and 3.7 moles of gas. What is the volume of gas in the sign?

Answer 1

This question would fall under chemistry - I would be surprised to find its answer in any biology course or text.

This is an ideal gas law equation problem. You must remember that "STP" means standard temperature and pressure, which are 0°C and 1 atm. You will need these values to plug in to the ideal gas law equation, which is:

PV = nRT

P = pressure

V = volume

n = moles

R = the ideal gas constant (a value you must look up, but be very careful about the units - they must match everything else you plug in to the equation)

T = temperature

In your problem, we know the following:

P = 1 atm (because of STP)

V = x

n = 3.7 moles

T = 0C° (because of STP)

Now we look at R values and decide which one to choose:

In thie case, we will use the R constant of 0.0821 because it has units of atm, L, moles, and Kelvin, which matches all but 1 of our variables

This means we need to convert our temperature to Kelvin (Celsius temp + 274.15 = Kelvin temp)

P = 1 atm (because of STP)

V = x Liters (because that is the volume unit in the R value that we chose)

n = 3.7 moles

R = 0.0821 (atm*L) / (mol*K)

T = 274.15 K (because of STP, we converted from Celsius to Kelvin)

Now plug in to the equation and solve:

(1 atm) (x Liters) = (3.7 moles) (0.0821 atm*L/mol*K) (274.15K)

(Divide both sides by 1 atm and now you have x)

x = 83 Liters (Final Answer)