Answer:
Pu-239
Explanation:
Beta decay moves the element which undergoes the decay one place to the right in the periodic table since to conserve charge and being beta radiations an electron we convert a neutron into a proton and an electron. In neutron capture we increase the atomic mas by one unit. We that in mind, lets solve the question:
U-238 + ₁⁰ n ⇒ U-239 ⇒ Np -239 + ₋₁⁰β ⇒ Pu-239 + ₋₁⁰β
The pH a 0.25 m solution of C₆H₅NH₂ is equal to 3.13.
<h3>How do we calculate pH of weak base?</h3>
pH of the weak base will be calculate by using the Henderson Hasselbalch equation as:
pH = pKb + log([HB⁺]/[B])
pKb = -log(1.8×10⁻⁶) = 5.7
Chemical reaction for C₆H₅NH₂ is:
C₆H₅NH₂ + H₂O → C₆H₅NH₃⁺ + OH⁻
Initial: 0.25 0 0
Change: -x x x
Equilibrium: 0.25-x x x
Base dissociation constant will be calculated as:
Kb = [C₆H₅NH₃⁺][OH⁻] / [C₆H₅NH₂]
Kb = x² / 0.25 - x
x is very small as compared to 0.25, so we neglect x from that term and by putting value of Kb, then the equation becomes:
1.8×10⁻⁶ = x² / 0.25
x² = (1.8×10⁻⁶)(0.25)
x = 0.67×10⁻³ M = [C₆H₅NH₃⁺]
On putting all these values on the above equation of pH, we get
pH = 5.7 + log(0.67×10⁻³/0.25)
pH = 3.13
Hence pH of the solution is 3.13.
To know more about Henderson Hasselbalch equation, visit the below link:
brainly.com/question/13651361
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<h3>
Answer:</h3>
498 kj/mol
<h3>
Explanation:</h3>
- Chemical reactions occur as a result of bond breaking and bond formation.
- The bonds in reactants are broken and atoms are rearranged to form new bonds.
- During bond breaking energy is absorbed to break the bonds of reactants while bond formation involves the release of energy during the formation of new bonds.
In our case;
In 1 mole of the Oxygen molecule, there is one O=O bond
Energy absorbed to break O=O is 498 kJ/mol
Therefore, the ΔH required to break all the bonds in one mole of Oxygen(O₂) molecules is 498kJ/mol.
Note that, bond breaking is endothermic since energy is absorbed from the surroundings.
