Asap 1) determine the hydronium and hydroxide ion concentrations in a solution that is 2.0 × 10-2 m naoh 2) determine the ph of a solution that is 5.0 × 10-4 m hno3+ 3) determine the ph of a 3.45 × 10-2 m sr(oh)2 solution. 4) the ph of a solution is determined to be 7.0. what is the hydronium ion concentration of this solution? 5) the ph of an aqueous solution is measured as 5.00 calculate the [h3o+] and the [oh-]. i've got the answers for each but i don't know if i'm correct and if i used correctly significant figures. , !

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1) Concentration of NaOH = 2.0 x 10⁻² M

Since NaOH is a monoacidic base,

The Hydroxide OH⁻ concentration will be the same as concentration of NaOH.

Concentration of hydroxide = [OH⁻] = 2.0 x 10⁻² M

We know the ionic product of water = 1.0 x 10⁻¹⁴

[H₃O⁺][OH⁻] = 1.0 x 10⁻¹⁴

Thus hydronium ion concentration [H₃O⁺] =

= 5.0 x 10⁻¹³ M

2) Concentration of HNO₃ = 5.0 x 10⁻⁴ M

Since HNO₃ is a monobasic acid,

[H₃O⁺] = 5.0 x 10⁻⁴ M

pH = - log [H₃O⁺] = - log [5.0 x 10⁻⁴]

= 3.3

3) Concentration of Sr(OH)₂ = 3.45 x 10⁻² M

Since Sr(OH)₂ is a diacidic base,

Concentration of OH⁻ = [OH⁻] = 2 x 3.45 x 10⁻² M

We know the ionic product of water = 1.00 x 10⁻¹⁴

[H₃O⁺][OH⁻] = 1.0 x 10⁻¹⁴

Thus hydronium ion concentration [H₃O⁺] =

= 1.45 x 10 ⁻¹³ M

pH = - log [H₃O⁺] = - log [1.45 x 10 ⁻¹³]

= 12.8

4) pH = 7.0

We know that [H₃O⁺] =

= 1.0 x 10⁻⁷ M

5) pH = 5.00

We know that [H₃O⁺] =

= 1.00 x 10⁻⁵ M

We know the ionic product of water = 1.0 x 10⁻¹⁴

[H₃O⁺][OH⁻] = 1.00 x 10⁻¹⁴

[OH⁻] =

= 1.00 x 10⁻⁹ M

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