Respuesta :

Answer:

[tex]1.628 M[/tex]

Explanation:

From the question we were given 0.155 moles of HBr, but Br and H are in ratio 1:1, then there are 0.155 moles of Br- ions.

We were also told that the solution contain NaBr, of 25.9 g. Then it must be converted to moles.

molar mass of NaBr =(22.99g + 79.90 )

= 102.89 g per mol.

the moles of NaBr can be calculated as 25.9 / 102.89

=0.252 moles

But Na and Br are in a ratio 1:1 , then there are 0.252 moles of Br-.

Then to get two Br- mol , we will add the first and second mol of Br- together

= 0.155 + 0.252

=0.407 moles.

The given solution has volume of 250 mL, but we know that there are 1000 ml in a liter, then if we convert to L for unit consistency we have

= 250/1000

= 0.25 L

molarity=0.407 moles/0.25 L

= 1.628 M.

Therefore, Br ion molarity is 1.628 M.

The molarity of the Br ions in the 250 ml solution has been 1.628 M.

Moles can be defined as the mass per unit molecular mass. Moles can be expressed as:

Moles = [tex]\rm \dfrac{weight}{molecular\;weight}[/tex]

Moles of NaBr = [tex]\rm \dfrac{25.9}{102.89}[/tex]

Moles of NaBr = 0.252 mol

Moles of HBr = 0.155 mol.

Since both the compounds have 1:1 ratio of atom: Br, the Br produced has been equal to the concentration of the compound.

Br from NaBr = 0.252 mol

Br from HBr = 0.155 mol.

Total Br ions = 0.407 mol.

Molarity can be expressed as:

Molarity = [tex]\rm moles\;\times\;\dfrac{1000}{Volume\;(ml)}[/tex]

Molarity of Br ions = 0.407 × [tex]\rm \dfrac{1000}{250\;ml}[/tex]

Molarity of Br ions = 1.628 M.

The molarity of the Br ions in the 250 ml solution has been 1.628 M.

For more information about the molarity, refer to the link:

https://brainly.com/question/12127540