What amount (in moles) of CO2 is contained in the 240.0 mL can of the soft drink?

funny thing.. this Wikipedia page

https://en.wikipedia.org/wiki/Henry%27s_law

showed Henry's law as

.. Pa = kHa x Ca

OR

.. Ca = kHa x Pa

depending on the way the constant is expressed.

where

.. Pa = partial pressure of component a in the gas phase

.. kHa = henry's law constant for the system

.. ca = concentration of component "a" in the liquid phase

until just recently. When someone felt the need to edit it and complicate it into oblivion. Henry's law is a simple equation. All of the rest of that stuff.. <sigh>

the only issue is.. which of those two equations

.. Pa = kHa x Ca

.. Ca = kHa x Pa

do you use?

You MUST look at the units of the constant to make that call.

**********

in this problem, the units of the constant

.. kH = 2.3x10^-2 mol / (L x atm)

i.e

.. kH = 2.3x10^-2 M / atm... .. .<=== recall that 1M = 1 mol / 1L

now.. if we look at the units of this equation.. Pa = kHa x Ca.

.. .. .. ...atm... .. .. ..... M.. ... .. ... ..M

.. .Pa [--- ---] ≠ kHa [---- --] x Ca [ -- ---]... .. .. [ ] indicates the UNITS

.. .. .... ..1.. ... .. ... .. .atm.. ... .. ... ..1

we see that

.. atm ≠ M/atm x M

this however does work out... you verify this!

.. .. .. ...M... .. .. ..... .. M.. ... .. ... .atm

.. .Ca [--- ---] ≠ kHa [---- --] x Pa [ -- ---]

.. .. .... ..1.. ... .. ... .. .atm.. ... .. ... ..1

meaning the form of the constant tells us to use this equation

.. Ca = kHa x Pa

the rest is simple

*********

0.240L x (2.3x10^-2 mol/Latm x 3.00atm) = 0.0166 mol CO2

n = (2.3 x 10^-2 mol/L-atm) (3.00 atm) (0.2400 L) = ____________ mol