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How many grams of krypton gas will occupy 2.55 liters at 1.25 atm if it occupies 3.75 liters at 0.750 atm at 255 K

User Basgys
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Answer:

There will be 94.7 grams of krypton gas

Step-by-step explanation:

Step 1: Data given

at 255K and 0.750 atm the volume is 3.75 L

At 1.25 atm the volume is 2.55 L

Molar mass of krypton = 83.798 g/mol

Step 2: Calculate number of moles

p*V = n*R*T

with p = the pressure of the krypton gas = 0.750 atm

with V = the volume of the krypton gas = 3.75 L

with n = the number of moles = TO BE DETERMINED

with R = the gasconstant = 0.08206 L*atm/ mol * K

with T = the temperature = 255 K

n = R*T / p*V

n = (0.08206 * 255)/ (0.750 * 3.75)

n = 0.744 moles

Step 3: Calculate new number of moles

P1*V1 = P2*V2

P1*V1 = n1*R*T

P2*V2 = n2*R*T

(P1*V1)/R*T = (P2*V2)/n2*R*T

Since R and T do not change we can write as followed:

(P1*V1) = (P2*V2) /n2

n2 = (P2*V2) / (P1*V1)

n2 = (2.55 *1.25)/(0.75*3.75)

n2 = 1.13 moles

Step 4: Calculate mass of krypton gas

mass = Number of moles * Molar mass

mass of krypton gas = 1.13 moles * 83.798 g/mol = 94.69 grams ≈ 94.7 grams

There will be 94.7 grams of krypton gas