Question

The "air" in the space suit of astronauts is actually pure oxygen supplied at a pressure of 0.30 bar. The two tanks on a space suit each have a volume of 3980. cm3 and have an initial pressure of 5860. kPa. Assuming a tank temperature of 16 C, what mass of oxygen is contained in the two tanks?

Answer 1

To find the mass of oxygen in the astronaut's space suit tanks, we convert the given volume and pressure to standard units, apply the Ideal Gas Law to find the number of moles, and use the molar mass of oxygen to calculate the mass as approximately 911.36 grams.

Step-by-step explanation:

To calculate the mass of oxygen in the tanks, we'll start by converting all the measurements to the same system, using the Ideal Gas Law represented by the equation PV = nRT, where P is pressure, V is volume, n is the amount of substance in moles, R is the ideal gas constant, and T is temperature.

First, we convert the volume from cm³ to liters (L):

Next, we convert the pressure from kPa to bar and then to atm, because the value of the ideal gas constant R is commonly given in these units:

We convert the temperature to Kelvin:

Now we use the Ideal Gas Law, with R = 0.08206 L atm / (mol K):

We calculate the mass of oxygen using the molar mass of O₂ (32.00 g/mol):

Therefore, the mass of oxygen in two tanks is approximately 911.36 grams.

Answer 2

There are 310.7 grams of O₂ in each tank

Step-by-step explanation:

To solve this problem we use PV=nRT. First we convert units:

• 16°C ⇒ 16+273.16 = 289.16 K

• 5860 kPa ⇒ 5860/101.325 = 57.83 atm

• 3980 cm³ ⇒ 3980/1000 = 3.98 L

We put the data in the equation and solve for n:

• 57.83 atm * 3.98 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 289.16 K

• n = 9.71 mol O₂

Finally we convert mol O₂ into mass:

• 9.71 mol O₂ * 32g/mol = 310.7 g O₂