That would be a decomposition reaction
I think the best answer from the given choices is option D. <span>Salt water is made up of more than one pure substance. It consists of salt and water. When each component exist alone in a container they are considered as pure substance however when mixed they are now a solution.</span>
It's B the atom has 4 neutrons and 4 protons because atom can be completed through the existence of neutron and proton which stay inside of the neuclues of atom
The reactions are a bit poorly written. While it's true that aqueous H₂CO₃ is produced in this neutralization reaction, the H₂CO₃ rapidly decomposes to yield CO₂(g) and H₂O(l). Writing the product as H₂CO₃(aq) in the net ionic equation is unnecessarily confusing since it portrays the substance as nonionizing yet water-soluble.
In any case, the Na⁺ and the Cl⁻ are the spectator ions here.
In a closed system, heat should be conserved which means that the heat produced in the calorimeter is equal to the heat released by the combustion reaction. We calculate as follows:
Heat of the combustion reaction = mC(T2-T1)
= 1 (1.50) (41-21)
= 30 kJ