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2 years ago

What is the pH of a solution of RbOH with a concentration of 0.86 M? Answer to 2 decimal places

Chemistry

1 answer:

lubasha [3.4K]2 years ago

3 0

Answer:The pH of the solution is given by pH=−log([H3O+])

Explanation:so you can't use

−

log

(

0.150

)

because that's the concentration of the hydroxide anions,

−

, not of the hydronium cations,

. In essence, you calculated the

pOH

of the solution, not its

Sodium hydroxide is a strong base, which means that it dissociates completely in aqueous solution to produce hydroxide anions in a

mole ratio.

NaOH

(

)

→

(

)

−

(

)

So your solution has

[

−

]

[

NaOH

]

0.150 M

Now, the

pOH

of the solution can be calculated by using

pOH

−

log

(

[

−

]

)

−−−−−−−−−−−−−−−−−−−−

In your case, you have

pOH

−

log

(

0.150

)

0.824

Now, an aqueous solution at

∘

has

pH + pOH

−−−−−−−−−−−−−−so you can't use

−

log

(

0.150

)

because that's the concentration of the hydroxide anions,

−

, not of the hydronium cations,

. In essence, you calculated the

pOH

of the solution, not its

Sodium hydroxide is a strong base, which means that it dissociates completely in aqueous solution to produce hydroxide anions in a

mole ratio.

NaOH

(

)

→

(

)

−

(

)

So your solution has

[

−

]

[

NaOH

]

0.150 M

Now, the

pOH

of the solution can be calculated by using

pOH

−

log

(

[

−

]

)

−−−−−−−−−−−−−−−−−−−−

In your case, you have

pOH

−

log

(

0.150

)

0.824

Now, an aqueous solution at

∘

has

pH + pOH

−−−−−−−−−−−−−−

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