Um to my best knowledge I believe it is the carbonated water
True. Covalent bonds involve sharing electrons to create a full valence shell.
it is water energy :) this is easy
A. would not help and maybe make it harder to get accurate measurements.
b. would make more delta T which will improve its accuracy
c. will also increase delta T.
To find the net ionic equation we must first write the balanced equation for the reaction. We must bear in mind that the reagents Ca(NO3)2 and Na2S are in the aqueous state and as product we will have CaS in the solid state, since it is not soluble in water and NaNO3 in the aqueous state.
The balanced equation of the reaction will be:

Ca(NO3)2(aq) + → Ca(aq) + 2Na(s)NO3Now, c(aq)ompounds in the aqueous state can be written in their ionic form, so the reaction will transform into:Na2S +

So, the answer will be option A