Question

Which 1.0 M acid solution has the largest concentration of hydronium [H3O+]?

HNO2

H2CO3

H2SO4

H3BO3

Answer 1

Keep in mind that these are all strong acids, so when they dissolve in water, the H+'s dissociate from the negative ion and bond with water to form the hydronium ion.

So...the largest concentration of hydronium (i.e. the most acidic solution) will be the one that produces the most H+ when dissolved. Which of your options fits?

Answer 2

H2SO4?

Answer 3

How many H+ ions does each option produce when dissolved?

Answer 4

i have no idea....

Answer 5

Start with the first.

HNO2 dissociates into H+ and NO2-. It only produces 1 H+ when dissolved in water.

H2CO3 dissociates into 2H+ and CO3(2-). It can produce 2 H+ when dissolved in water, and so would be a stronger acid compared to HNO2.

What about the others?

Answer 6

i dont know how to find what is dissociates into

Answer 7

im so lost..

Answer 8

Just remember that the H's are always positive ions and the rest of the molecule is the negative ion. Dissociation means the ions split apart.

HNO3 has 1 H, so 1 H splits off when it dissolves.
H2CO3 has 2 H's, so 2 H's split off when it dissolves.

What about the other two?

Answer 9

so the 3rd one has 2 H's and the fourth one has 3 H's?

Answer 10

Right! So which of the 4 options produces the MOST H's when it dissolves in water?

Answer 11

H3BO3?

Answer 12

Yup!

Answer 13

thank you so much! i understand now

Answer 14

it was wrong though.. @matt101

Answer 15

boric acid is pretty weak acid though, it wont dissociate to 100% in pure water