Question

What types of chemical reactions are the following
1. 2H2O ---> 2H2+O2
2. 2C2H6+7O2 ----> 4 CO2 + 6H2O
3. 2Na+CL2---->2 NaCI
4. 4AIBr3+3O2---> 2 Al2O3+6Br2
5.KCI+NaI--->KI+NaCI
Choices
A. Double Replacement
B. Deomposition
C. Single Replacement
D. Synthesis
E. Combustion

Answer 1

Let's categorize each of the reactions you've provided:

1. **2H2O ---> 2H2 + O2**
- This is a **Decomposition** reaction because water (H2O) is breaking down into hydrogen (H2) and oxygen (O2).

2. **2C2H6 + 7O2 ----> 4 CO2 + 6H2O**
- This is a **Combustion** reaction because it involves the burning of a hydrocarbon (C2H6, ethane) in the presence of oxygen (O2), producing carbon dioxide (CO2) and water (H2O).

3. **2Na + Cl2 ----> 2 NaCl**
- This is a **Synthesis** reaction because sodium (Na) and chlorine gas (Cl2) combine to form sodium chloride (NaCl).

4. **4AlBr3 + 3O2 ----> 2 Al2O3 + 6Br2**
- This is a **Single Replacement** reaction because it involves the replacement of bromine with oxygen; however, it more closely resembles a reaction that leads to the formation of products from elemental and compound reactants.

5. **KCl + NaI ----> KI + NaCl**
- This is a **Double Replacement** reaction because the potassium (K) and sodium (Na) ions are swapping partners with the chloride (Cl) and iodide (I) ions.

In summary:

1. **Decomposition** (B)
2. **Combustion** (E)
3. **Synthesis** (D)
4. **Single Replacement** (C) or could also be considered **Combustion** if viewed as a different type based on the context.
5. **Double Replacement** (A)