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At what pressure in atm does ethane (C₂H₆) have a density of 37.2 g/L at 61.8 °C?

At what temperature (in K) does uranium hexafluoride have a density of 0.6480 g/L at 0.5073 atm?

Answer both questions please

User Schabluk
by
7.7k points

2 Answers

1 vote

Answer:

Step-by-step explanation:

To find the pressure of ethane (C₂H₆) at a given density and temperature, we can use the ideal gas law, which is expressed as:

PV = nRT

where:

P = pressure (in atm)

V = volume (in L)

n = number of moles of gas

R = gas constant (0.0821 L·atm/(mol·K))

T = temperature (in Kelvin)

We need to convert the density (in g/L) to molar mass (g/mol) in order to calculate the number of moles (n). The molar mass of ethane (C₂H₆) is:

Molar mass of C₂H₆ = 2(12.01 g/mol) + 6(1.01 g/mol) = 30.07 g/mol

Now, let's calculate the number of moles (n) using the given density:

Density of ethane (C₂H₆) = 37.2 g/L

Number of moles (n) = Density / Molar mass

n = 37.2 g/L / 30.07 g/mol

Next, we'll convert the temperature from Celsius to Kelvin:

Temperature (in K) = 61.8 °C + 273.15 K/°C

Temperature (in K) ≈ 334.95 K

Now, we can rearrange the ideal gas law to solve for pressure (P):

P = nRT / V

Given that V = 1 L (since the density is given per liter), let's plug in the values:

P = (37.2 g/L / 30.07 g/mol) * (0.0821 L·atm/(mol·K)) * 334.95 K / 1 L

P ≈ 1.53 atm

So, ethane (C₂H₆) has a density of 37.2 g/L at 61.8 °C at a pressure of approximately 1.53 atm.

Now, let's find the temperature (in Kelvin) at which uranium hexafluoride (UF₆) has a density of 0.6480 g/L at 0.5073 atm.

Again, we'll use the ideal gas law:

P = nRT / V

Given density of uranium hexafluoride (UF₆) = 0.6480 g/L

Pressure (P) = 0.5073 atm

We need to calculate the number of moles (n) of UF₆. To do this, we first need to find the molar mass of UF₆:

Molar mass of UF₆ = (1 mol of U) + 6(1 mol of F) = 238.03 g/mol + 6(18.998 g/mol) = 352.03 g/mol

Number of moles (n) = Density / Molar mass

n = 0.6480 g/L / 352.03 g/mol

Now, let's rearrange the ideal gas law to solve for temperature (T):

T = PV / (nR)

Given V = 1 L (since the density is given per liter), let's plug in the values:

T = (0.5073 atm) * (1 L) / ((0.6480 g/L / 352.03 g/mol) * 0.0821 L·atm/(mol·K))

T ≈ 12.87 K

So, uranium hexafluoride (UF₆) has a density of 0.6480 g/L at approximately 12.87 K at a pressure of 0.5073 atm.

User Javier Figueroa
by
8.2k points
1 vote

To determine the pressure at which ethane (C₂H₆) has a density of 37.2 g/L at 61.8 °C, we can use the ideal gas law:

=

PV=nRT

where:

P = pressure in atm

V = volume in liters (given as 37.2 g/L)

n = number of moles (we'll assume 1 mole for simplicity)

R = ideal gas constant (0.0821 L.atm/mol.K)

T = temperature in Kelvin (convert 61.8 °C to Kelvin)

First, let's convert the temperature to Kelvin:

(

)

=

61.8

°

+

273.15

=

334.95

T(K)=61.8°C+273.15=334.95K

Now, we can rearrange the ideal gas law to solve for pressure:

=

P=

V

nRT

Substitute the values:

=

(

1

)

(

0.0821

.

/

.

)

(

334.95

)

37.2

/

=

27.537195

.

37.2

0.7408

P=

37.2g/L

(1mol)(0.0821L.atm/mol.K)(334.95K)

=

37.2g

27.537195L.atm

≈0.7408atm

So, at approximately 0.7408 atm, ethane (C₂H₆) will have a density of 37.2 g/L at 61.8 °C.

Next, to determine the temperature (in Kelvin) at which uranium hexafluoride (UF₆) has a density of 0.6480 g/L at 0.5073 atm, we'll use the same ideal gas law equation:

=

PV=nRT

where:

P = pressure in atm (given as 0.5073 atm)

V = volume in liters (given as 0.6480 g/L)

n = number of moles (we'll assume 1 mole for simplicity)

R = ideal gas constant (0.0821 L.atm/mol.K)

Rearrange the equation to solve for temperature (in Kelvin):

=

T=

nR

PV

Substitute the given values:

=

(

0.5073

)

(

0.6480

/

)

(

1

)

(

0.0821

.

/

.

)

0.04008

T=

(1mol)(0.0821L.atm/mol.K)

(0.5073atm)(0.6480g/L)

≈0.04008K

So, at approximately 0.04008 Kelvin, uranium hexafluoride (UF₆) will have a density of 0.6480 g/L at 0.5073 atm. However, this temperature is extremely low, close to absolute zero, which seems unlikely. It is possible that there may be an error in the data or calculation. Please double-check the values and units to ensure accuracy.

User Khizar Hayat
by
8.5k points