Question

If it requires 48.3 milliliters of 0.55 molar nitric acid to neutralize 15.0 milliliters of barium hydroxide, solve for the molarity of the barium hydroxide solution. Show all of the work used to solve this problem.

Unbalanced equation: Ba(OH)2 + HNO3 Ba(NO3)2 + H2O

Answer 1

@aaronq @abb0t

Answer 2

Do you know how each one would dissociate?

Ba(OH)2 ->?

HNO3 ->?

Answer 3

no not at all

Answer 4

lol well i guess you don't need to know for this problem, do you care to know?

Answer 5

if you think it will help yes if not its ok :)

Answer 6

wait you do need to know this..

you basically need to know the charges of each ion..
Barium would be a divalent cation .. that is, it would carry a +2 charge, I'm sure you know hydroxide has a -1 charge:

so it dissociates like this: Ba(OH)2 -> Ba2+ + 2OH-

and nitric acid like this: HNO3 -> NO3- + H+

good?


for the question you need to find how many moles of nitric acid you used

using Molarity = moles of solute/Liters of solution

plug stuff in (48.3 milliliters of 0.55 molar nitric acid)
then when you know how many moles you used (neutralized)

NOW notice that in a neutralization reaction

OH- + H+ -> H2O

since you produce 2 times OH for every mole of Ba(OH)2 .. you need to multiply the number of moles you got by 2...

use the same equation, plug in the moles you got from the multiplication and the volume to find the molarity:

molarity= moles/L

Answer 7

so the answer is what?

Answer 8

what you calculate?

Answer 9

i dont even know how to set up the equation

Answer 10

@seiga

Answer 11

if you read what i typed you will

Answer 12

0.55/48.3?

Answer 13

molar means molarity a measure of concentration

Answer 14

and you need to convert mL to L, since that's how molarity is defined

Answer 15

how do i get millileters to L do i times 48.3 times 10 or 100?

Answer 16

1 L = 1000 mL

1 mL = 0.001 L

Answer 17

lol what grade are you in?

Answer 18

10th so 48.3 ml is 0483 l right?

Answer 19

0.0483

Answer 20

* 0.0483

Answer 21

ok so 0.55/0.0483?

Answer 22

nope 0.55 is the molarity (M)

Molarity= moles/ L of solution

Answer 23

so what do i do then?

Answer 24

0.55 = x / 0.0483?

Answer 25

yep, find the moles of base (OH-) you neutralized

Answer 26

so 0.55 x 0.0483 = 0.026565

Answer 27

now since Ba(OH)2 gives 2 OH- per molecule

multiply that number by 2

Answer 28

0.026565 x 2 =0.05313

Answer 29

so you have 0.05313 moles and 15.0 millilitres

now use the same formula, plug in and solve for molarity:

Molarity = moles / L of solution


don't forget to convert

Answer 30

units mL to L

Answer 31

15 milileters = 0.015 l right
and 0.05323 / 0.015 = 3.542

Answer 32

wait pellet, you were supposed to divide the number of moles by 2, not multiply, sorry dude

Answer 33

so 0.55 x 0.0483 = 0.026565

divide by 2

then plug into M=moles/L equation

Answer 34

ok so 0.026565 / 2 = 0.0132825

15 milileters = 0.015 l right
and 0.0132825 / 0.015 =0.8855

Answer 35

yep thats right

Answer 36

thanks a lot

Answer 37

no prob dude

Answer 38

this stuff is really not hard, you shouldn't be scared of the math. just try stuff

Answer 39

ok i think im gonna practise

Answer 40

do it up

Answer 41

Ba(OH)2 + 2 HNO3 → Ba(NO3)2 + 2 H2O

(48.3 mL) x (0.55 M) x (1/2) / (15.0 mL) = 0.886 M Ba(OH)2

Answer 42

The first thing to note is that the barium ion is 2+ whereas the nitrate ion is -1. So nitric acid only has one hydrogen ion to donate whereas barium hydroxide has two hydroxyl ions. This means you would need twice as much nitric acid than you might expect: Ba(OH)2 + 2 HNO3. The number of moles of nitric acid is 0.0483 multiplied by 0.55M or 0.0266 moles. Dividing this number of moles by 15 ml or 0.015l gives 1.77M but there are two hydroxides per Barium hydroxide molecule and so the concentration is half or 0.886M.
Ba(OH)2+2HNO3−→Ba(NO3)22H2O

Answer 43

hope this helped.

Answer 44

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