If 2.64g of CO2 dissolves in 500ml water at 25°C, what is the Kh(Henry's law constant) for CO2? The total pressure is 3340 mmHg and air pressure at 25°C is 680 torr.

I would be better if you used the same screen name.

Apparently there is no standard Kh. I will use the one that is
p = Kc*C but C = K*pgas is also used.
p is 3340-680 mm. Convert to atm.
Kc is the constant.
C is the molarity. You will want mols = grams/molarmass and M = mols/L. Substitute and solve for Kc. K in one equation is the reciprocal of that in the other equation. The units for the one I've used is L*atm/mol.

To find the Kh (Henry's law constant) for CO2, we can use Henry's law equation:

P = Kh * C

where P is the partial pressure of the gas, Kh is the Henry's law constant, and C is the concentration of the gas in the solution.

First, let's convert the total pressure of 3340 mmHg to torr:
3340 mmHg = 3340 torr

Next, let's calculate the concentration of CO2 in the solution:
C = (mass of CO2) / (molar mass of CO2 * volume of water)
= 2.64 g / (44.01 g/mol * 0.5 L)
= 0.120 mol/L

Now we can plug in the values into the Henry's law equation and solve for Kh:

P = 680 torr
C = 0.120 mol/L

Kh = P / C
= 680 torr / 0.120 mol/L
= 5666.67 torr * L/mol

Therefore, the Kh (Henrys's law constant) for CO2 is 5666.67 torr * L/mol.

To find the Henry's law constant (Kh) for CO2, we need to use the formula:

Kh = (P_CO2) / (C_CO2)

Where:
- P_CO2 is the partial pressure of CO2 in the mixture (in this case, the dissolved CO2 in water)
- C_CO2 is the concentration of CO2 in the mixture

First, let's calculate the partial pressure of CO2 using the total pressure and the air pressure at 25°C:

Partial pressure of CO2 = Total pressure - Air pressure
Partial pressure of CO2 = (3340 mmHg) - (680 torr), let's convert the pressure units to a single unit (mmHg):
Partial pressure of CO2 = (3340 mmHg) - (680 mmHg)
Partial pressure of CO2 = 2660 mmHg

Next, we'll calculate the concentration of CO2 in the mixture. Given that 2.64g of CO2 dissolves in 500ml of water, we can use the following formula:

C_CO2 = (mass of solute) / (volume of solution)

C_CO2 = 2.64g / 500ml, but let's convert the volume to liters (1 ml = 0.001 L):
C_CO2 = 2.64g / 0.5L
C_CO2 = 5.28 g/L

Now we can calculate the Henry's law constant (Kh):

Kh = (P_CO2) / (C_CO2)
Kh = (2660 mmHg) / (5.28 g/L), but the unit of pressure should be in atm, so let's convert the pressure from mmHg to atm:
Kh = (2660 mmHg) / (760 mmHg/atm)
Kh = 3.5 atm

Therefore, the Kh (Henry's law constant) for CO2 in this case is 3.5 atm.