which must be the same when comparing 1 mol of oxygen gas, o₂, with 1 mol of carbon monoxide gas, co?\n○ the…

which must be the same when comparing 1 mol of oxygen gas, o₂, with 1 mol of carbon monoxide gas, co?\n○ the mass\n○ the volume\n○ the number of molecules\n○ the number of oxygen atoms
Answer
may differ.
Step4: Analyze oxygen atoms
1 mol $\text{O}_2$ has $2 \times 6.022 \times 10^{23}$ O atoms; 1 mol $\text{CO}$ has $1 \times 6.022 \times 10^{23}$ O atoms. Counts differ.
Step5: Analyze molecule count
1 mol $\text{O}_2$ and 1 mol $\text{CO}$ each have $6.022 \times 10^{23}$ molecules. Counts are equal.