Complete the following reactions,
(i) `H_2(g)+MnO(s)overset(Delta)rarrMn(s)+H_2O(g)`
(ii) `CO(g)+H_2(g)underset("Catalyst")overset(Delta)rarr`
(iii) `C_3H_8(g)+3H_2O(g)underset("Catalyst")overset(Delta)rarr`
(iv) `Zn(s)+NaOH(aq)overset("Heat")rarr`
After completing the above reactions in the balanced equations the coefficient for `H_2(g)` may be

Options

A. 0,0,7,1
B. 1,2,4,2
C. 1,2,1,1
D. 1,3,4,2

Answer

To complete the reactions and find the coefficients for \( H_2(g) \), we will analyze each reaction step by step.

### Step 1: Analyze the first reaction
**Reaction:**
\[ H_2(g) + MnO(s) \overset{\Delta}{\rightarrow} Mn(s) + H_2O(g) \]

- This reaction is already balanced.
- The coefficient of \( H_2(g) \) in this reaction is **1**.

### Step 2: Analyze the second reaction
**Reaction:**
\[ CO(g) + H_2(g) \underset{\text{Catalyst}}{\overset{\Delta}{\rightarrow}} CH_3OH(g) \]

- This reaction also involves \( H_2(g) \).
- The balanced equation is:
\[ CO(g) + 2H_2(g) \rightarrow CH_3OH(g) \]
- The coefficient of \( H_2(g) \) here is **2**.

### Step 3: Analyze the third reaction
**Reaction:**
\[ C_3H_8(g) + 3H_2O(g) \underset{\text{Catalyst}}{\overset{\Delta}{\rightarrow}} 3CO(g) + 7H_2(g) \]

- The balanced equation shows that the products include \( 7H_2(g) \).
- Therefore, the coefficient of \( H_2(g) \) in this reaction is **7**.

### Step 4: Analyze the fourth reaction
**Reaction:**
\[ Zn(s) + NaOH(aq) \overset{\text{Heat}}{\rightarrow} Na_2ZnO_2 + H_2(g) \]

- The balanced equation shows that \( H_2(g) \) is produced.
- The coefficient of \( H_2(g) \) in this reaction is **1**.

### Summary of Coefficients
- From the first reaction: **1**
- From the second reaction: **2**
- From the third reaction: **7**
- From the fourth reaction: **1**

### Total Coefficient of \( H_2(g) \)
Adding these coefficients together:
\[ 1 + 2 + 7 + 1 = 11 \]

### Final Answer
The total coefficient for \( H_2(g) \) in the completed reactions is **11**.