Assertion(A) Combustion of 16g of methane give18 g of water.
Reason(R) in the combustion of methane, water is one of the products.

Options

A. Both A and R are true and R is the correct explnanation of A.
B. A is true but R is false.
C. A is false but R is true.
D. Both A and R are flase.

Explanation

To solve the assertion and reason question regarding the combustion of methane, we will follow these steps:

### Step 1: Write the balanced chemical equation for the combustion of methane.
The combustion of methane (CH₄) can be represented by the following balanced equation:

\[ \text{CH}_4 + 2 \text{O}_2 \rightarrow \text{CO}_2 + 2 \text{H}_2\text{O} \]

### Step 2: Identify the mass of methane and the expected mass of water produced.
According to the question, the assertion states that the combustion of 16 grams of methane produces 18 grams of water.

### Step 3: Calculate the molar mass of methane (CH₄).
To find the molar mass of methane:
- Carbon (C) has an atomic mass of 12 g/mol.
- Hydrogen (H) has an atomic mass of 1 g/mol, and there are 4 hydrogen atoms in methane.

Calculating the molar mass:
\[ \text{Molar mass of CH}_4 = 12 + (4 \times 1) = 12 + 4 = 16 \text{ g/mol} \]

### Step 4: Calculate the molar mass of water (H₂O).
To find the molar mass of water:
- Hydrogen (H) has an atomic mass of 1 g/mol, and there are 2 hydrogen atoms in water.
- Oxygen (O) has an atomic mass of 16 g/mol.

Calculating the molar mass:
\[ \text{Molar mass of H}_2\text{O} = (2 \times 1) + 16 = 2 + 16 = 18 \text{ g/mol} \]

### Step 5: Determine the amount of water produced from the combustion of methane.
From the balanced equation, 1 mole of methane produces 2 moles of water. Therefore, if 16 grams (1 mole) of methane is combusted, it will produce:

\[ 2 \text{ moles of H}_2\text{O} = 2 \times 18 \text{ g/mol} = 36 \text{ grams of water} \]

### Step 6: Compare the calculated mass of water with the assertion.
The assertion states that 16 grams of methane produces 18 grams of water, which is incorrect. The actual amount of water produced is 36 grams.

### Step 7: Evaluate the reason.
The reason states that water is one of the products of the combustion of methane, which is true as per the balanced equation.

### Conclusion:
- The assertion (A) is **false** because 16 grams of methane produces 36 grams of water, not 18 grams.
- The reason (R) is **true** because water is indeed a product of the combustion of methane.

Thus, the correct answer is that the assertion is false, and the reason is true.

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