Answer : The enthalpy change of reaction is -23.9 kJ
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given final reaction is,
The intermediate balanced chemical reaction will be,
(1)
(2)
First we will reverse the reaction 1 and multiply equation 2 by 3 then adding both the equation, we get :
(1)
(2)
The expression for final enthalpy is,
Therefore, the enthalpy change of reaction is -23.9 kJ
I believe the correct answer would be the last option. When an electrons moves from an excited state to the ground state, it would release energy. An electron in the excited state would mean that it contains high kinetic energy so to move to a lower state some of these energy should be released.
The (valence) electrons of an atom because they're the most moveable particles of the atom...they are found on the valence shells and can move, unlike the protons and neutrons which are enclosed in the nucleus of the atom.
Answer:
<h3>The answer is 13.87 g</h3>
Explanation:
The mass of a substance when given the density and volume can be found by using the formula
<h3>mass = Density × volume</h3>
From the question
density of metal = 5.78 g/mL
volume = final volume of water - initial volume of water
volume = 24.7 - 22.3 = 2.4 mL
We have
mass = 5.78 × 2.4 = 13.872
We have the final answer as
<h3>13.87 g</h3>
Hope this helps you
Moles of Na theoretically extract : 10.256
<h3>Further explanation</h3>
Given
600 g of NaCl
Required
moles of Na
Solution
Na can be electrolyzed from NaCl(molten)
Na⁺ + e⁻⇒ Na
Cl⁻⇒1/2 Cl₂ + e⁻
Overall reaction :
NaCl⇒Na + 1/2 Cl₂ x2
<em>2NaCl⇒2Na + Cl₂</em>
mol of NaCl(MW=58.5 g/mol) :
= 600 g : 58.5 g/mol
= 10.256
From the equation, mol ratio of NaCl : Na = 2 : 1, so :
mol Na = mol NaCl = 10.256