Answer:- B- 
Explanations:- Sharing of electrons takes place between non metals and the bond formed by the sharing of electrons is known as covalent bond. In first choice we only have a zinc metal and so no sharing of electrons would be possible here.
In third choice we have NaCl. Na is a metal and Cl is a non metal. The property of metals is to transfer its valence electrons to the non metal and the bond formed is known as ionic bond. So, third choice is also not correct.
In choice B we have sulfate ion that has sulfur and oxygen atoms and both of these are non metals. So, sharing of electrons is present here between the S and O atoms and covalent bonds are formed.
So, choice B-
is the right answer.
Due to the 3. Gulf Stream
This question is describing two chemical equations whereby the concentration of ammonia has to be determined. The first reaction is between 25.00 mL of ammonia and 50.00 mL of 0.100-M HCl whose excess was neutralized with 21.50 mL of 0.050-M Na₂CO₃ and thus, the concentration ammonia in the cloudy solution was determined as 0.114 M.
First of all we need to go over the titration of the excess HCl with Na₂CO₃ by writing the chemical equation it takes place when they react:

Whereas the mole ratio of HCl to Na₂CO₃ is 2:1 and the volume of the HCl leftover is determined as follows:

Next, we infer that the consumed volume of HCl by the ammonia solution was:

Then, we write the chemical equation that takes place between ammonia and HCl:

Whereas the mole ratio is now 1:1, which means that the concentration of ammonia was:

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<span>Colbat (ii) which is a compound birth out of the combination of chlorine and colbat to form Cocl2.6h2o has water in it as we can see from it's chemical it's hexahydrate
Anhydrous cobalt chloride as the word anhydrous clearly states , does not have water in</span>