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3 years ago

4. Calculate AH for the reaction

Chemistry

1 answer:

Naddik [55]3 years ago

7 0

Answer:

ΔH = -111.1kJ

Explanation:

ΔH of any reaction could be obtained from similar reaction doing algebraic operations. Using the reactions:

<em>(1) </em>CaO(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(l) ΔH = -186 kJ

<em>(2) </em>CaO(s) + H₂O(l) → Ca(OH)₂(s) ΔH = -62.3 kJ

<em>(3) </em>Ca(OH)₂(s) → Ca(OH)₂(aq) ΔH = - 12.6 kJ

(1) - (2):

Ca(OH)₂(s) + 2HCl(aq) → CaCl₂(aq) + 2H₂O(l)

ΔH = -186kJ - (-62.3kJ) = -123.7kJ

This reaction -(3):

Ca(OH)₂(aq) + 2HCl(aq) → CaCl₂(aq) + 2H₂O(l)

ΔH = -123.7kJ - (-12.6kJ) = -111.1kJ

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Answer:

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Explanation:

All isotope decay follows the equation:

ln [A] = -kt + ln [A]₀

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We can find k from half-life as follows:

k = ln 2 / Half-Life

k = ln2 / 27.7 days

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[A]₀ = 39.7mg

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ln[A] = 2.476

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Answer:

Dipole, less electronegativity, higher electronegativity

Explanation:

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Answer:

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Explanation:

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Aloiza [94]

Answer:

To determine the enthalpy and entropy of dissolving a compound, you need to measure the Ksp at multiple temperatures. Then, plot ln(Ksp) vs. 1/T. The slope of the plotted line relates to the enthalpy (ΔH) of dissolving and the intercept of the plotted line relates to the entropy (ΔS) of dissolving.

Explanation:

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$\Delta G=-RTln(Ksp)\\\\\Delta G=\Delta H-T\Delta S$