Atoms and Molecules

Q2. A molecule of oxygen gas is O2.

Q3. Avogadro number represents the number of particles in one mole.

Q4. Isotopes have different atomic numbers.

Q5. Atoms contain a nucleus and electrons.

Q6. Mass is conserved in a closed chemical reaction system.

Q7. One mole of O₂ and one mole of N₂ contain different numbers of molecules.

Q8. At conventional STP, one mole of gas occupies about 22.4 L.

Q9. An element can be broken into simpler substances by ordinary chemical methods.

Q10. A molecule can consist of two or more atoms.