The right answer is D. all of the above.
The restoration and rehabilitation of wetlands are today major challenges to maintain a fabric of natural spaces with high heritage value. The ecological engineering that has developed over many years, inspired by methods of renaturation of coastal, alluvial, grassland and forest natural areas has specificities that it is necessary to share to allow access to the greatest number. This knowledge is built on the basis of feedback and scientific knowledge, which is itself constantly evolving. They constitute a base for conducting sustainable operations that are consistent with the maintenance of ecological trajectories as close as possible to the natural model in balance with human activities.
b. buffer
c. acid
d. catalyst
Answer:
Explanation:
The best choice to prepare a buffer of pH 9.0 is a conjugate acid/base pair in which the acid has pKₐ = 9.0 ± 1.
Let's examine each of the choices.
A. NH₃/NH₄Cl
For NH₃, = pK_b = 4.75
For NH₄⁺, pKₐ 14.00 - 4.75 = 9.25
B. HCHO₂/NaCHO₂
For HCHO₂, pKₐ = 3.74
C. C₅H₅N/ C₅H₅NHCl
For C₅H₅N, = pK_b = 8.76
For C₅H₅N⁺, pKₐ 14.00 – 8.76 = 5.21
D. HNO₂/NaNO₂
For HNO₂, pKₐ = 3.33
The only acid with a pKₐ close to 9.0 is the ammonium ion.
The best buffer to prepare a buffer with pH 9.0 is
From the given options, the best combination to prepare a buffer with a PH of 9.0 is given by;
Option 1; NH₃;NH₄Cl
Now, we want to find the best choice to prepare a buffer of pH 9.0. Thus, let us look at each option;
Option 1; NH₃;NH₄Cl
We are given that pK_b for NH₃ is 4.75
Thus pKₐ for NH₄ is;
NH₄; pKₐ = 14.00 - 4.75
NH₄; pKₐ = 9.25
Option 2; HCHO₂; NaCHO₂
We are given that pK_a for HCHO₂ is 3.74
HCHO₂; pKₐ = 3.74
Option 3;C₅H₅N; C₅H₅NHCl
We are given that pK_b for C₅H₅N is 8.76
Thus
For C₅H₅N, = pK_b = 8.76
Thus, pKₐ for C₅H₅N is;
C₅H₅N; pKₐ = 14.00 – 8.76
C₅H₅N; pKₐ = 5.21
Option 4; HNO₂;NaNO₂
We are given pKₐ for HNO₂ as 3.33
HNO₂; pKₐ = 3.33
Looking at all the pKₐ values, the only acid that has a pKₐ close to 9.0 is NH₄ with a pKₐ of 9.25.
In conclusion, the best combination to prepare a buffer with pH of 9.0 is
NH₃;NH₄Cl
Read more at; brainly.com/question/15592723
solution of NaNO?
Answer:
1.25 moles NaNO
Explanation:
Molarity = moles/Volume (L)
moles = Molarity (M) x Volume (L)
M = 2.5 M
V = 500 mL = 0.5L
moles = M x V = 2.5 x 0.5 = 1.25 moles
The minimum energy required to start a reaction is called activation energy (A.E.).
(Option C)
Activation energy is the energy barrier that reactant molecules must overcome to transform into products during a chemical reaction.
It is the energy difference between the energy levels of the reactants and the transition state on the reaction's potential energy diagram.
Enthalpy (E1 and E2) and heat of reaction are related to the energy changes during the course of a reaction but are not directly related to the energy barrier required to initiate the reaction.
Enthalpy (H) refers to the total heat content of a system, while heat of reaction (ΔH) represents the energy difference between the products and reactants at constant pressure.
Learn more about activation energy here: brainly.com/question/1380484
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