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3 years ago

Why does thermal energy decreases when potassium is dissolved in water

Chemistry

1 answer:

Levart [38]3 years ago

8 0

Answer:

The process of dissolving can be endothermic (temperature goes down) or exothermic (temperature goes up).

When water dissolves a substance, the water molecules attract and “bond” to the particles (molecules or ions) of the substance causing the particles to separate from each other.

The “bond” that a water molecule makes is not a covalent or ionic bond. It is a strong attraction caused by water’s polarity.

It takes energy to break the bonds between the molecules or ions of the solute.

Energy is released when water molecules bond to the solute molecules or ions.

If it takes more energy to separate the particles of the solute than is released when the water molecules bond to the particles, then the temperature goes down (endothermic).

If it takes less energy to separate the particles of the solute than is released when the water molecules bond to the particles, then the temperature goes up (exothermic).

Explanation:

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Now, converting $oz to gm$

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Now, for determining the number of moles, the formula for number of moles is:

$number of moles = \frac{given mass}{Molar mass}$

Substituting the values:

$number of moles = \frac{28.066}{196.967} = 0.1425 mole$

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Since 1 atom of gold has 79 electrons so,

Number of electrons = $0.8581 \times 10^{23}\times 79 = 67.7899\times 10^{23} electrons$

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3 years ago

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Answer:

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Explanation:

Hello there!

In this case, for these particle-mole-mass relationships problems, it is necessary for us to recall the following equivalence statement, based off the molar mass of the involved compound, C3H8, one mole of particles and the Avogadro's number:

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3 years ago

Why does thermal energy decreases when potassium is dissolved in water​

Why does thermal energy decreases when potassium is dissolved in water