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Why is sodium hydroxide in water exothermic?
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Kwaku Asare
Why is sodium hydroxide in water exothermic?
The dissolving of sodium hydroxide (NaOH) in water can be divided into two sequential processes:
Firstly, energy is absorbed to separate the Na⁺ and OH⁻ in the lattice of sodium hydroxide into free Na⁺ and OH⁻ ions. Na⁺Cl⁻(s) → Na⁺(g) + Cl⁻(g) …… ΔH₁ > 0
Secondly, energy is released when the free Na⁺ and OH⁻ ions undergoes hydration. Na⁺(g) + Cl⁻(g) → Na⁺(aq) + Cl⁻(aq) …… ΔH₂ < 0
As the energy released in hydration of the Na⁺ and OH⁻ ions is greater than the energy absorbed to separate the Na⁺ and OH⁻ ions in the lattice, heat is released in the overall process. In other words, the dissolving of sodium hydroxide is exothermic.
The dissolving of sodium hydroxide (NaOH) in water can be divided into two sequential processes:
Firstly, energy is absorbed to separate the Na⁺ and OH⁻ in the lattice of sodium hydroxide into free Na⁺ and OH⁻ ions. Na⁺Cl⁻(s) → Na⁺(g) + Cl⁻(g) …… ΔH₁ > 0
Secondly, energy is released when the free Na⁺ and OH⁻ ions undergoes hydration. Na⁺(g) + Cl⁻(g) → Na⁺(aq) + Cl⁻(aq) …… ΔH₂ < 0
As the energy released in hydration of the Na⁺ and OH⁻ ions is greater than the energy absorbed to separate the Na⁺ and OH⁻ ions in the lattice, heat is released in the overall process. In other words, the dissolving of sodium hydroxide is exothermic.
The PROCESS of dissolving NaOH solid into water is exothermic because the ionic (charge) monopoles represented by the (separated) ions create electric fields which give rise to strong hydrogen bonds with polar water molecules due to their large dipole moments.
This energy state (NaOH dissolved in water) is much lower than that achieved in the solid NaOH crystal, and the regular hydrogen bonding in pure water.
The PROCESS of dissolving NaOH solid into water is exothermic because the ionic (charge) monopoles represented by the (separated) ions create electric fields which give rise to strong hydrogen bonds with polar water molecules due to their large dipole moments.
This energy state (NaOH dissolved in water) is much lower than that achieved in the solid NaOH crystal, and the regular hydrogen bonding in pure water.
The dissolving of sodium hydroxide (NaOH) in water can be divided into two sequential processes:
Firstly, energy is absorbed to separate the Na⁺ and OH⁻ in the lattice of sodium hydroxide into free Na⁺ and OH⁻ ions.
Na⁺Cl⁻(s) → Na⁺(g) + Cl⁻(g) …… ΔH₁ > 0
Secondly, energy is released when the free Na⁺ and OH⁻ ions undergoes hydration.
Na⁺(g) + Cl⁻(g) → Na⁺(aq) + Cl⁻(aq) …… ΔH₂ < 0
As the energy released in hydration of the Na⁺ and OH⁻ ions is greater than the energy absorbed to separate the Na⁺ and OH⁻ ions in the lattice, heat is released in the overall process. In other words, the dissolving of sodium hydroxide is exothermic.
The dissolving of sodium hydroxide (NaOH) in water can be divided into two sequential processes:
Firstly, energy is absorbed to separate the Na⁺ and OH⁻ in the lattice of sodium hydroxide into free Na⁺ and OH⁻ ions.
Na⁺Cl⁻(s) → Na⁺(g) + Cl⁻(g) …… ΔH₁ > 0
Secondly, energy is released when the free Na⁺ and OH⁻ ions undergoes hydration.
Na⁺(g) + Cl⁻(g) → Na⁺(aq) + Cl⁻(aq) …… ΔH₂ < 0
As the energy released in hydration of the Na⁺ and OH⁻ ions is greater than the energy absorbed to separate the Na⁺ and OH⁻ ions in the lattice, heat is released in the overall process. In other words, the dissolving of sodium hydroxide is exothermic.
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Let thge mass of NaOH = X g
The mass of water = 200 g
The mass of solution = ( 200 + X) g
%(m/m) = mass of solute / mass of solution * 100 %
X / ( 200 + x) * 100 % = 4 %
100 X = 4(200 + X)
100 X = 800 + 4 X
96 X = 800
X = 8.33 g NaOH required,
Let thge mass of NaOH = X g
The mass of water = 200 g
The mass of solution = ( 200 + X) g
%(m/m) = mass of solute / mass of solution * 100 %
X / ( 200 + x) * 100 % = 4 %
100 X = 4(200 + X)
100 X = 800 + 4 X
96 X = 800
X = 8.33 g NaOH required,
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I’m pretty sure it’s just some of the NaOH solution that has been aerosolised by the violent dissolution. It’s not some other compound or something.
I’m pretty sure it’s just some of the NaOH solution that has been aerosolised by the violent dissolution. It’s not some other compound or something.
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The PROCESS of dissolving NaOH solid into water is exothermic because the ionic (charge) monopoles represented by the (separated) ions create electric fields which give rise to strong hydrogen bonds with polar water molecules due to their large dipole moments.
This energy state (NaOH dissolved in water) is much lower than that achieved in the solid NaOH crystal, and the regular hydrogen bonding in pure water.
The PROCESS of dissolving NaOH solid into water is exothermic because the ionic (charge) monopoles represented by the (separated) ions create electric fields which give rise to strong hydrogen bonds with polar water molecules due to their large dipole moments.
This energy state (NaOH dissolved in water) is much lower than that achieved in the solid NaOH crystal, and the regular hydrogen bonding in pure water.
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VOTE