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Crazy boy [7]
3 years ago
12

Given that it requires 27.9 ml of 0.270 m na2s2o3(aq) to titrate a 15.0-ml sample of i3–(aq), calculate the molarity of i3–(aq)

in the solution.
Chemistry
1 answer:
Digiron [165]3 years ago
6 0

The molar concentration of the KI_3 solution is 0.251 mol/L.

<em>Step 1</em>. Write the <em>balanced chemical equation</em>

I_3^(-) + 2S_2O_3^(2-) → 3I^(-) + S_4O_6^(2-)

<em>Step 2</em>. Calculate the <em>moles of S_2O_3^(2-)</em>

Moles of S_2O_3^(2-)

= 27.9 mL S_2O_3^(2-) ×[0.270 mmol S_2O_3^(2-)/(1 mL S_2O_3^(2-)]

= 7.533 mmol S_2O_3^(2-)

<em>Step 3</em>. Calculate the <em>moles of I_3^(-) </em>

Moles of I_3^(-) = 7.533 mmol S_2O_3^(2-)))) × [1 mmol I_3^(-)/(2 mmol S_2O_3^(2-)] = 3.766 mmol I_3^(-)

<em>Step 4</em>. Calculate the <em>molar concentration of the I_3^(-) </em>

<em>c</em> = "moles"/"litres" = 3.766 mmol/15.0 mL = 0.251 mol/L

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Gala2k [10]

Answer:

HOAc is stronger acid than HClO

ClO⁻ is stronger conjugate base than OAc⁻

Kb(OAc⁻) = 5.5 x 10⁻¹⁰

Kb(ClO⁻) = 3.3 x 10⁻⁷

Explanation:

Assume 0.10M HOAc => H⁺ + OAc⁻  with Ka = 1.8 x 10⁻⁵

=> [H⁺] = √Ka·[Acid] =√(1.8 x 10⁻⁵)(0.10) M = 1.3 x 10⁻³M H⁺

Assume 0.10M HClO => H⁺ + ClO⁻ with Ka = 3 x 10⁻⁸

=> [H⁺] = √(3 x 10⁻⁸)(0.10)M = 5.47 x 10⁻⁵M H⁺

HOAc delivers more H⁺ than HClO and is more acidic.

Kb = Kw/Ka, Kw = 1 x 10⁻¹⁴

Kb(OAc⁻) = 5.5 x 10⁻¹⁰

Kb(ClO⁻) = 3.3 x 10⁻⁷

4 0
3 years ago
Heat is transferred by conduction through a wall of thickness 0.87 m. What is the rate of heat transfer if the walls thermal con
erik [133]

Explanation:

The given data is as follows.

         Thickness (dx) = 0.87 m,       thermal conductivity (k) = 13 W/m-K

        Surface area (A) = 5 m^{2},       T_{1} = 14^{o}C

        T_{2} = 93^{o}C

According to Fourier's law,

                    Q = -kA \frac{dT}{dx}

Hence, putting the given values into the above formula as follows.

                      Q = -kA \frac{dT}{dx}

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Therefore, we can conclude that the rate of heat transfer is 5902.298 W.

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Answer:

The false statement is: 3. Because liquid water and liquid carbon tetrachloride do not mix, neither do their vapors

Explanation:

Gas is a state of matter, that has <u>less density than liquids and solids</u>. The gaseous particles have low intermolecular forces and thus they can move freely.

It is a very <u>compressible fluid</u> that has no fixed shape. Gas occupies the whole container in which it is stored, thus taking the shape of the container. Therefore, <u>the volume of the gas is equal to the volume of the container.</u>

<u>Polar liquid like water (H₂O) and nonpolar liquid like carbon tetrachloride, are immiscible. However, in the gaseous state, their vapors form a  homogeneous mixture.</u>

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3 years ago
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Answer:

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It is endergonic

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It is being catalyzed by an enzyme

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