Question

The Henry's law constant for helium gas in water at 30${}^o$C is $3.70\times {10}^{-4}$M/atm. When the partial pressure of helium above a sample of water is 0.650 atm, the concentration of helium in the water is ................ M.

• A. $5.69\times {10}^{-4}$
• B. $1.76\times {10}^3$
• C. 1.3
• D. $2.41\times {10}^{-4}$
• E. $3.70\times {10}^{-4}$

Answer 1

The correct option is D $2.41\times {10}^{-4}$

According to Henry's law, $S=KP$
S is the solubility in moles per litre
K is the henry's law constant
P is the pressure in atm.
Substitute values in the above expression.
$S=3.70\times {10}^{-4}\times 0.650atm$
$K_H=2.41\times {10}^{-4}$