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2 years ago

7. A solution containing 90grams of KNO3 per 100. grams of H2O at

Chemistry

1 answer:

Tomtit [17]2 years ago

5 0

Answer:

(4) concentrated and supersaturated

Explanation:

At 50.°C, 90g of KNO3 lies above the solubility curve [on the Regents Reference Table G]. This indicates that the solution is supersaturated, meaning it contains more solute than will naturally dissolve, and was formed when a saturated solution cooled. Furthermore, the percent concentration of this solution is 90% KNO3 making this solution concentrated. This can be calculated using the formula for mass percent concentration.

Percent Mass = <u>Mass of Solute (g)</u> x 100

Mass of Solution (g)

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Step2247 [10]

Answer:

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2 years ago

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Solution :

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First we have to calculate the standard electrode potential of the cell.

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Now we have to calculate the standard Gibbs free energy.

Formula used :

$\Delta G^o=-nFE^o_{cell}$

where,

$\Delta G^o$ = standard Gibbs free energy = ?

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Now put all the given values in this formula, we get the Gibbs free energy.

$\Delta G^o=-(2\times 96500\times (-0.47))=+90710J/mole=+90.71kJ/mole\approx +91kJ/mole$

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