Ratio of H and O by weight in `H_(2)O` is

Options

A. `2:1`
B. `1:6`
C. `1:8`
D. `8:1`

Explanation

To find the ratio of hydrogen (H) and oxygen (O) by weight in water (H₂O), we can follow these steps:

### Step 1: Identify the number of atoms of each element in the molecule
In one molecule of water (H₂O), there are:
- 2 hydrogen atoms
- 1 oxygen atom

### Step 2: Determine the atomic masses of hydrogen and oxygen
- The atomic mass of hydrogen (H) is approximately 1 g/mol.
- The atomic mass of oxygen (O) is approximately 16 g/mol.

### Step 3: Calculate the total mass of hydrogen in the molecule
To find the total mass of hydrogen in H₂O:
- Total mass of hydrogen = Number of hydrogen atoms × Atomic mass of hydrogen
- Total mass of hydrogen = 2 × 1 g/mol = 2 g

### Step 4: Calculate the total mass of oxygen in the molecule
To find the total mass of oxygen in H₂O:
- Total mass of oxygen = Number of oxygen atoms × Atomic mass of oxygen
- Total mass of oxygen = 1 × 16 g/mol = 16 g

### Step 5: Write the ratio of hydrogen to oxygen by weight
Now we can write the ratio of the total mass of hydrogen to the total mass of oxygen:
- Ratio of H to O = Total mass of hydrogen : Total mass of oxygen
- Ratio of H to O = 2 g : 16 g

### Step 6: Simplify the ratio
To simplify the ratio:
- Divide both sides by 2:
- Ratio of H to O = 1 : 8

### Final Answer
The ratio of hydrogen to oxygen by weight in H₂O is **1 : 8**.

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