Answer:
Step-by-step explanation:
When comparing 1 mole of oxygen gas (O2) with 1 mole of carbon monoxide gas (CO), the one thing that must be the same is the number of molecules.
In 1 mole of any substance, there is Avogadro's number of molecules, which is approximately 6.022 x 10^23 molecules. This is a fundamental concept in chemistry, where 1 mole of any substance contains the same number of entities, whether they are atoms, molecules, ions, or other particles.
So, when comparing 1 mole of oxygen gas (O2) with 1 mole of carbon monoxide gas (CO), the number of molecules in both cases will be the same, approximately 6.022 x 10^23 molecules. This principle holds true for any substance, regardless of its chemical composition.