Question

How much oxygen does a plant give off?

Answer 1

Really it depends on the size and the amount of carbon it takes in. If you're talking about an average house plant, it gives off about 5 mL of oxygen per hour. If you're talking about a plant along the lines of a large tree or bush, it gives off about 260 pounds of oxygen a year.

Answer 2

5ml of oxygen per hour when it is growing.