Question
sulfuric acid is a strong acid and dissociates in water as shown in reaction
H2SO4(aq)=2H^+(aq)+SO4^2-(aq)
what is the hydrogen ion concentration, in mol dm^-3,when 1.50g of sulfuric acid is dissolved in water to give 0.500dm^3 of solution ?show all of your working and give your answer to three significant figures.
H2SO4(aq)=2H^+(aq)+SO4^2-(aq)
what is the hydrogen ion concentration, in mol dm^-3,when 1.50g of sulfuric acid is dissolved in water to give 0.500dm^3 of solution ?show all of your working and give your answer to three significant figures.
Answers
DrBob222
Hello zak. What level is this course? If you want an approximate answer, and from the ionization equation in the problem I think that is what you want, it is as follows:
mols H2SO4 = 1.50g/molar mass H2SO4 = about 0.015 but you need to be more accurate.
mols H^+ = twice that (from two hydrogen ions/molecule)= ?.
Then (H) in M = mols/L = ?/0.500 = xx?.
In reality it is less than that because H2SO4 is not a strong acid EXCEPT for the first ionization; i.e., the second ionization has a k2 = about 0.012. If you take that into account (H^+) = about 0.04M instead of about 0.06M.
mols H2SO4 = 1.50g/molar mass H2SO4 = about 0.015 but you need to be more accurate.
mols H^+ = twice that (from two hydrogen ions/molecule)= ?.
Then (H) in M = mols/L = ?/0.500 = xx?.
In reality it is less than that because H2SO4 is not a strong acid EXCEPT for the first ionization; i.e., the second ionization has a k2 = about 0.012. If you take that into account (H^+) = about 0.04M instead of about 0.06M.