4. So, now that you know what you know from questions 1-3, how much liquid sevoflurane should I inject into the expiratory limb of a closed 10 liter anesthetic circuit to produce a 2% concentration?

Answer: 1.2 ml

2% of 10 liters is 200 ml of vapor.

Density of sevoflurane = 1.52 gm/ml and MW = 200 gms/mole. Therefore 1.52 ÷ 200 X 22.4 liters of vapor per mole of vapor = 170 ml of vapor per ml of liquid.

200 ÷ 170 = 1.2 ml