The phase change H₂(g) → H₂(s) is called deposition, and the enthalpy change, ΔH, for this phase change has a negative (-) sign.
Deposition<span> is a </span>thermodynamic process<span> in which </span>gas<span> transforms into </span>solid<span> without passing through the </span>liquid phase<span>. Example is formin snow in clouds directly from water vapor. In deposition energy is released.</span>
Answer : The balanced half-reaction in a basic solution will be,
Explanation :
Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.
Rules for the balanced chemical equation in basic solution are :
First we have to write into the two half-reactions.
Now balance the main atoms in the reaction.
Now balance the hydrogen and oxygen atoms on both the sides of the reaction.
If the oxygen atoms are not balanced on both the sides then adding water molecules at that side where the more number of oxygen are present.
If the hydrogen atoms are not balanced on both the sides then adding hydroxide ion
at that side where the less number of hydrogen are present.
Now balance the charge.
![H_2O(l)\rightarrow H_2O_2(aq)](https://tex.z-dn.net/?f=H_2O%28l%29%5Crightarrow%20H_2O_2%28aq%29)
- Now balance the oxygen atoms.
![H_2O(l)\rightarrow H_2O_2(aq)+H_2O(l)](https://tex.z-dn.net/?f=H_2O%28l%29%5Crightarrow%20H_2O_2%28aq%29%2BH_2O%28l%29)
- Now balance the hydrogen atoms.
![H_2O(l)+2OH^-(aq)\rightarrow H_2O_2(aq)+H_2O(l)](https://tex.z-dn.net/?f=H_2O%28l%29%2B2OH%5E-%28aq%29%5Crightarrow%20H_2O_2%28aq%29%2BH_2O%28l%29)
![H_2O(l)+2OH^-(aq)\rightarrow H_2O_2(aq)+H_2O(l)+2e^-](https://tex.z-dn.net/?f=H_2O%28l%29%2B2OH%5E-%28aq%29%5Crightarrow%20H_2O_2%28aq%29%2BH_2O%28l%29%2B2e%5E-)
The balanced half-reaction in a basic solution will be,
![2OH^-(aq)\rightarrow H_2O_2(aq)+2e^-](https://tex.z-dn.net/?f=2OH%5E-%28aq%29%5Crightarrow%20H_2O_2%28aq%29%2B2e%5E-)
There are 115 protons in the element 115 and due to the large number of protons, the element does not exist in nature.
Also, the element can not be isolated in nature that is IUPAC had to require an independent confirmation of the element.
<h3>What is element 115?</h3>
We know that the periodic table is an arrangement of the atoms in order of increasing atomic number. We know that the larger the atomic number of the element, the less likely that the element would be stable in nature. The element that have been named 115 is called Moscovium and was discovered in Moscow as a product of a radioactive experiment. The number of protons in element 115 is 115 protons
Generally, the element number 115 does not exist in nature because if the proton number in an element exceeds 82, the repulsion between the protons would make it almost impossible for the nucleus to be a stable nucleus.
The reason why IUPAC had to request an independent confirmation of the element is because it does not exist in nature.
Learn more about element 115:brainly.com/question/27914234
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Answer:
10moles
Explanation:
mole ratio = 8:16
therefore
1 mole Li2S forms 2 moles Li
when 5 moles Li2S reacts
5 moles Li2S = 5 x 2 moles Li
= 10 moles Li
alpha decay is an emission of ₂⁴He
nucleus. If an element undergoes an alpha decay, the mass of the daughter
nucleus formed is reduced by 4 compared to mass of parent atom and atomic
number is reduced by 2 compared to atomic number of parent atom.
Let's assume that the parent atom is X, atomic number is z and mass number is A. Then the formed daughter nucleus, Y should have atomic number as z-2 and mass number as A-4.
The equation is
(z) (A)X → ₂⁴α + (z-2)(A-4)Y
Example:
₉₄²³⁹Pu → ₂⁴α + ₉₂<span>²³⁵U</span>