Answer:
Covalent
Explanation:
Covalent is the sharing of electrons and Ionic is transferring of electrons.
Answer:
Cells are the basic structural and functional unit of life.
I think the correct answer would be negative change in enthalpy, low temperature and negative entropy. Freezing of water is an exothermic process which means heat is released to the surroundings so negative enthalpy. And this is seen in the change to a lower temperature. Entropy is negative which signifies that there is more order as water freezes.
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.
