Answer:
All of the above.
Explanation:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.
This process is not reversible and a change of energy that is sometimes heat is given off.
For the answer to the question above, well presumably because the exact concentration of the composition KMnO4 solution doesn't matter. <span>If the concentration of the KMnO4 solution is important (usually in titrations etc.) then it is not allowed to use a wet bottle. The water in the bottle will dilute the KMnO4 solution and change the concentration of the said compound.</span>
Answer:
CaCO₃(s) → CaO(s) + CO₂(g)
Explanation:
The decomposition reaction always make two compounds from one.
The products always have simpler chemical structure, originated from a determined compound. This can happens spontaneously or by a third party.
A notable example of decomposition is hydrolysis. As for example the case of water, which decomposes and generates oxygen and hydrogen gas
2H₂O (l) → 2 H₂ (g) + O₂ (g)
In this case, the calium carbonate decomposes into CaO and CO₂
These two, are the products of the decomposition.
Of course, the unique reactant is the Calcium Carbonate
The balanced equation is:
CaCO₃(s) → CaO(s) + CO₂(g)
