<span>In crystallography, the terms crystal system, crystal family, and lattice system each refer to one ... In total there are seven crystal systems: triclinic, monoclinic, orthorhombic, ..... A polar crystal possess a "unique" axis (found in no other directions) such ... lattices in three dimensions; each can apply in one lattice system only.</span><span>
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I believe the answer is D
The answer is the 3rd choice
Question 1:
(a) Sulfurous acid: H2SO3
Sulfuric acid: H2SO4
(b) Nitrous acid: H2NO2
Nitric acid: H2NO3
Question 2:
To calculate the pH, based on concentration of H+ ions, there is one formula:

So the pH of this solution is

(the solution is basic).