10618 G of an Unknown Salt Is Dissolved in a Coffee

question 45

Multiple Choice

10.618 g of an unknown salt is dissolved in a coffee cup calorimeter that contains 50.0 mL of water. The measured temperature decreased from 23.8 °C to 22.7 °C. Identify the unknown salt. The specific heat of water is 4.184 J g^-1 °C^-1, and assume the density of the solution is 1.00 g mL^-1.

• A) NaF, H = 0.91 kJ mol^-1
• B) NaBr, H = -0.60 kJ mol^-1
• C) NaNO₃, H = 20.50 kJ mol^-1
• D) LiNO₃, H = -2.51 kJ mol^-1
• E) LiBr∙2H₂O, H = -23.26 kJ mol^-1

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Definitions:

High-Pressure

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