Consider two equal-volume balloons under the same conditions of temperature and pressure. One contains helium, and the other contains carbon dioxide.

Which of the following are the SAME for these two gas samples. Select all choices that apply.

Number of gas particles (atoms or molecules)

Density

Number of moles of gas

Average kinetic energy

Average particle velocity

Mass

1. Number of gas particles (atoms or molecules)

2. Number of moles of gas

3. Average kinetic energy

Explanation:

Since the two gas has the same volume and are under the same conditions of temperature and pressure,

Then:

1. They have the same number of mole because 1 mole of any gas at stp occupies 22.4L. Now both gas will occupy the same volume because they have the same number of mole

2. Since they have the same number of mole, then they both contain the same number of molecules as explained by Avogadro's hypothesis which states that at the same temperature and pressure, 1 mole of any substance contains 6.02x10^23 molecules or atoms.

3. Being under the same conditions of temperature and pressure, they both have the same average kinetic energy. The kinetic energy of gas is directly proportional to the temperature. Now that both gas are under same temperature, their average kinetic energy are the same.

catya that's not even a b or c