How many moles are equal to 3.6 x10 to the 23 power molecules of oxygen gas O2?

One mole is 6.02 × 1023 of anything. One mole of atoms is 6.02 × 1023 atoms, one mole of rice is 6.02 × 1023 grains, one mole of shoes is 6.02 × 1023 shoes.

So you multiply 23 with 6.02 × 1023 to get 1.38 × 1025