Answer:
Check explanation for answer
Step-by-step explanation:
Let's analyze each reaction per separate and explain the reason of the type of reaction:
a) CH₃CH₂CH₃ + 5O₂ -------> 3CO₂ + 4H₂O
Type of reaction: Combustion
In this case, the combustion is a reaction where a compound reacts with a molecule of oxygen to produce, in almost every case, CO₂ and H₂O. Therefore, this reaction can only be a combustion. It cannot be combination because combination requires two compounds to be combined and formed, in most of the cases, one product. In this case we have two. It can be similar to a double displacement but not combination.
b) KOH + HClO₄ --------> KClO₄ + H₂O
Type of reaction: Acid base reaction, double displacement.
This is clearly an acid base reaction cause we have an acid (HClO₄) reacting with a base (KOH) to produce a salt and water. It's also a double displacement reaction, because as you can see, the atom of Potassium (K) is displacing the H, and the H displaces the K simultaneously, and form two new products.
c) CH₃CH₂OH + 3O₂ -------> 2CO₂ + 3H₂O
Type of reaction: Combustion
The reason, the same for case a).
d) CuSO₄ + ZnCrO₄ ---------> CuCrO₄ + ZnSO₄
Type of reaction: Double displacement and precipitation
In this case, it's pretty similar to case b), The Cu replaces the Zn in the CrO₄, while the Zn replaces the Cu with the SO₄. But it's also a precipitation because the CuCrO₄ that was formed is in solid state, and if the reactants were in aqueous state and a solid was formed, this means that this solid is precipitating from the reaction. Therefore, it's a precipitation reaction too.
Hope this helps