Question

How many grams of O₂ are there in 40 liters of O₂?​

Answer 1

To answer this question, we need to know the relationship between liters and grams of oxygen. This depends on the pressure and temperature of the oxygen. At standard temperature and pressure (STP), which is defined as 0°C and 1 atmosphere of pressure, one mole of any gas occupies 22.4 liters.

The molar mass of oxygen (O₂) is approximately 32 g/mol. Therefore, one mole of oxygen gas (O₂) weighs 32 grams.

We can use these values to calculate the number of grams of oxygen in 40 liters of O₂ at STP:

Calculate the number of moles of O₂ in 40 liters:
40 liters ÷ 22.4 liters/mol = 1.79 moles of O₂
Calculate the number of grams of O₂ in 1.79 moles:
1.79 moles × 32 g/mol = 57.3 g of O₂
Therefore, there are approximately 57.3 grams of O₂ in 40 liters of O₂ at STP.

Answer 2

We can use the ideal gas law to solve this problem:

PV = nRT

where P is pressure, V is volume, n is the number of moles of gas, R is the gas constant, and T is temperature.

We can rearrange this equation to solve for n:

n = PV/RT

For a gas at standard temperature and pressure (STP), which is 0°C and 1 atmosphere of pressure, one mole of gas occupies 22.4 liters of volume. So we can use this conversion factor to convert from volume to moles.

1 mole O₂ = 22.4 L O₂ at STP

We can use this conversion factor to find the number of moles of O₂ in 40 liters:

n = (40 L) / (22.4 L/mol) = 1.79 mol

Now we can use the molar mass of O₂ to convert from moles to grams:

1 mole O₂ = 32 g O₂

mass of O₂ = n x molar mass = 1.79 mol x 32 g/mol = 57.3 g

So there are 57.3 grams of O₂ in 40 liters of O₂ at STP.