What is the hydrogen ion concentration, in mol dm−3, when 2.00 g of sulfuric acid is dissolved in water to give 0.400 dm3 of solution? could you explain in a simple and clear way please because im not very good at chemistry. thanks in advance
How advanced is this class. If it is very beginning, I would answer,
.....H2SO4 ==> 2H^+ + SO4^2-
So 0.4M = 0.8M H^+.
If this is not a VERY VERY beginning class, that answer is not right. Why? Because the second ionization of H2SO4 is not 100% as is the first.
.....H2SO4 ==> H^+ +HSO4^-
This is 100% since H2SO4 is a strong acid. So (H+) from this is 0.4M.
There is a second ionization for HSO4^-. It is not strong.
........HSO4^- ==> H^+ + SO4^2-
I.......0.4........0......0
C.......-x.........x......x
E.......0.4-x......x......x
k2 = 0.012 = (H^+)(SO4^2-)/(HSO4^-)
Therefore, the H^+ will be the total of 0.4M from the first ionization and whatever the second one is BUT the amount from the second one is too small to change the total significantly. I can show you how to solve the second one if you wish but not tonight.
i have never used the ice table before so i think its basic class. so do i just add those 2 numbers together? Thanks DrBob
Sure! To find the hydrogen ion concentration, we need to use the formula for molarity (M) which is the amount of solute divided by the volume of the solution.
First, we need to convert the mass of sulfuric acid (2.00 g) to moles. To do this, we need to know the molar mass of sulfuric acid. The molar mass of sulfuric acid is 98.09 g/mol.
So, the number of moles of sulfuric acid can be calculated using the formula: moles = mass / molar mass.
moles = 2.00 g / 98.09 g/mol ≈ 0.0204 mol.
Next, we need to calculate the volume of the solution. The volume given is 0.400 dm³.
Now, we can use the formula for molarity: Molarity (M) = moles / volume.
Molarity = 0.0204 mol / 0.400 dm³.
To get the value in mol dm⁻³ (moles per cubic decimeter), we divide the number of moles by the volume in dm³.
Molarity = 0.0204 mol / 0.400 dm³ ≈ 0.051 mol dm⁻³.
Therefore, the hydrogen ion concentration in the solution is approximately 0.051 mol dm⁻³.
Remember to check your calculations and units to make sure they are correct!