The reactant is chosen by you; also the study of products of the reaction give information about the initial compound.
2
1
Just one.
Two
decomposition reaction has only one reactant
Combustion. Any reaction that has O2 as a reactant is combustion.
If you mean Zn + H2SO4 --> ZnSO4 + H2, then no, it is not a decomposition reaction. In decomposition reactions one reactant is broken down into two or more simpler substances. For example, the electrolysis of water, 2H2O --> 2H2 + O2 is a decomposition reaction. The reaction referred to in your question is a double replacement (displacement) reaction. I apologize that the subscripts are not working at this time.
A chemical reaction that breaks down a compound into simpler products is a decomposition reaction. For example, when electrolyzed, water will be decomposed into hydrogen and oxygen gas. Decomposition reactions involve one reactant and multiple products.
A Decomposition Reaction, Single Replacement Reactions, Double Replacement Reactions and Combustion Reactions...
decomposition reaction has only one reactant
In decomposition reaction, single reactant will breakdown to form two or more products.
A chemical reaction that is classified as decomposition
Decomposition reactions always have one complex reactant and two or more simpler products.
there is a difference between decompositon reaction and to decompose the reaction mixture in (for example ice/HCl) n'mixture which for lmiting the excess reagents
Combustion. Any reaction that has O2 as a reactant is combustion.
Decomposition reactions are those in which one reactant splits into two or more products. Only those decomposition reaction are redox reactions in which minimum one of the products is an element.Example-2 H2O ---> 2H2 + O2
A decomposition reaction takes one reactant and makes multiple products. AB -> A + B
If you mean Zn + H2SO4 --> ZnSO4 + H2, then no, it is not a decomposition reaction. In decomposition reactions one reactant is broken down into two or more simpler substances. For example, the electrolysis of water, 2H2O --> 2H2 + O2 is a decomposition reaction. The reaction referred to in your question is a double replacement (displacement) reaction. I apologize that the subscripts are not working at this time.
A Decomposition Reaction, Single Replacement Reactions, Double Replacement Reactions and Combustion Reactions...
It is synthesis since your adding them together other wise decomposition is breaking them apart
The decomposition reaction is:MgCO3 = MgO + CO2