These gases all have similar properties under standard conditions: they are all odorless, colorless, monatomic gases with very low chemical reactivity. The six noble gases that occur naturally are helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and Radon (Rn).
If you need help, then ask yourself what you need..
Answer:
22.656 grams of oxygen gas are there in a 2.3L tank at 7.5 atm and 24° C
Explanation:
An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law:
P * V = n * R * T
where R is the molar constant of the gases and n the number of moles.
In this case you know:
- R= 0.082

- T= 24 °C= 297 °K (being 0°C=273°K)
Replacing:

Solving:

n=0.708 moles
Knowing that oxygen gas is a diatomic gas of molecular form O₂ and its mass is 32 g / mole, you can apply the following rule of three: if 1 mole contains 32 grams, 0.708 moles, how much mass will it have?

mass= 22.656 grams
<u><em>22.656 grams of oxygen gas are there in a 2.3L tank at 7.5 atm and 24° C</em></u>
Remember this:
atomic mass= atomic number + number of neutrons
The atomic number (same thing as number of protons) in this case is 15. The atomic mass is 31.
So, we subtract 15 from 31 to find the number of neutrons.
31-15=16
16 neutrons!!!