One of the best buffer choice for pH = 8.0 is Tris with Ka value of 6.3 x 10^-9.
To support this answer, we first calculate for the pKa value as the negative logarithm of the Ka value:
pKa = -log Ka
For Tris, which is an abbreviation for 2-Amino-2-hydroxymethyl-propane-1,3 -diol and has a Ka value of 6.3 x 10^-9, the pKa is
pKa = -log Ka
= -log (6.3x10^-9)
= 8.2
We know that buffers work best when pH is equal to pKa:
pKa = 8.2 = pH
Therefore Tris would be a best buffer at pH = 8.0.
If it is located at the second to last row of the periodic table (the halogen family), has seven electrons on it's outer shell, and has an oxidation number of -1, it is a halogen.
Hope this helps : D
Answer:
There will be one Al3+ ion.
There will be 3 NO3- ions
Explanation:
Dissociation equation:
Al(NO₃)₃ → Al³⁺ + 3NO₃¹⁻
When aluminium nitrate dissociate it produces one silver ion (Al³⁺) and three (NO₃¹⁻) ions.
Properties of Al(NO₃)₃:
It is inorganic compound having molecular mass 169.87 g/mol.
It is white odor less compound.
Its density is 4.35 g/mL.
Its melting and boiling points are 120°C and 440°C.
It is soluble in water.
It is sued to treat infections.
It is used in the photographic films.
It s toxic and must be handled with great care.
Is there answer choices ??
Reaction 3 is the double displacement reaction.
Double displacement reaction occurs when the negatively and the positively charged ions of the compounds interchange their position when the new compound in the product is formed.
<h3>Which is a double displacement reaction?</h3>
In the <u>first reaction</u>, the element lead (Pb) is not an ion and no exchange of the cations or the anions occurs hence it is not a double displacement reaction.
In the <u>second reaction</u>, one compound is getting split into two new compounds and is a decomposition reaction.
In the <u>third reaction</u>,
in
and
in
are anions and cations and exchanges their places to produce two new compounds 
In the <u>fourth reaction</u>, a single compound is generated as the result of the combination reaction and hence, it is not the double displacement reaction.
Therefore,
is the double displacement reaction.
Learn more about double displacement reaction here:
brainly.com/question/10091171