Question

The Henry's law constant for oxygen is 1.3 x 10⁻³ mol dm⁻³ atm⁻¹. If partial pressure of oxygen is 0.46 atmosphere, what is the concentration of dissolved oxygen at 25°C and 1 atm pressure?

• A. 2.82 x 10⁻³ mol dm⁻³
• B. 5.98 x 10⁻⁴ mol dm⁻³
• C. 3.53 x 10⁻⁴ mol dm⁻³
• D. 5.98 mol dm⁻³

Answer 1

Answer: (B)

5.98 x 10⁻⁴ mol dm⁻³

Answer 2

Henry’s law for a gas in solution is given by:

C = kH × p

where

kH = 1.3 × 10⁻³ mol dm⁻³ atm⁻¹ p = 0.46 atm

Substitute the values:

C = 1.3 × 10⁻³ × 0.46 = 5.98 × 10⁻⁴ mol dm⁻³.