Question

If 1.240 g of carbon dioxide dissolves in 1.01 l of water at 755 mm hg, what quantity of carbon dioxide (in grams) will dissolve at 790 mm hg?

Answer 1

Answer : 1.297 g carbon dioxide will dissolve at 790 mm Hg

Explanation :

According to Henry's law, the amount of gas dissolved in water at a given temperature is directly proportional to its vapor pressure .

In equation format the law can be written as

$C_{gas}= K\times P_{gas}$

Here C is the concentration of the gas

P is the partial pressure of the gas

K is known as Henry's constant which is temperature dependent.

At 2 different partial pressure values, the equation can be modified as follows

$\frac{C_{1}}{C_{2}}= \frac{P_{1}}{P_{2}}$

Let us calculate C₁

C₁ = amount of gas in grams / L

C₁ = 1.240 g / 1.01 L

C₁ = 1.228 g/L

P₁ = 755 mm Hg

P₂ = 790 mm Hg

C₂ = ?

Let us plug in the values in Henry's equation

1.228 g L⁻¹ / C₂ = 755 mm Hg / 790 mm Hg

1.228 g L⁻¹ / C₂ = 0.956

C₂ = 1.228 g L⁻¹ / 0.956

C₂ = 1.285 g L⁻¹

The concentration of carbon dioxide at 790 mm Hg is 1.285 g/L

We have 1.01 L water.

Therefore the amount of gas dissolved = 1.01 L x 1.285 g/L = 1.297 g

1.297 g carbon dioxide will dissolve at 790 mm Hg in 1.01 L water

Answer 2

Your answer is gonna be 1.297.