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2 years ago

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The molar heat of fusion of gold is 12.550 kJ mol–1. At its melting point, how much mass of melted gold must solidify to release

235.0 kJ of energy?

1 answer:

RideAnS [48]2 years ago

6 0

The mass of melted gold to release the energy would be 3, 688. 8 Kg

<h3>How to determine the mass</h3>

We have quantity of energy is;

Q = n × HF

n = number of moles

HF = heat of fusion

Let's find number of moles

235.0 = n × 12.550

number of moles = $\frac{235}{12. 550}$ = 18. 725 moles

Note that molar mass of Gold is 197g/ mol

Number of moles = mass/ molar mass

Mass = number of moles × molar mass

Mass = 18. 725 × 197

Mass = 3, 688. 8 Kg

Thus, the mass of melted gold to release the energy would be 3, 688. 8 Kg

Learn more about molar heat of fusion here:

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<u>Explanation:</u>

Mass defect is defined as the difference in the mass of an isotope and its mass number.

The equation used to calculate mass defect follows:

$\Delta m=[(n_p\times m_p)+(n_n\times m_n)]-M$

where,

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We are given:

An isotope of phosphorus which is $_{15}^{31}\textrm{P}$

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Putting values in above equation, we get:

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3 years ago

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