Number of milli moles in 1.0 gram of water

Options

A. 1
B. 18
C. 55.55
D. 100

Explanation

To find the number of millimoles in 1.0 gram of water, we can follow these steps:

### Step 1: Determine the molar mass of water (H₂O).
- Water consists of two hydrogen atoms and one oxygen atom.
- The molar mass of hydrogen (H) is approximately 1 g/mol, and the molar mass of oxygen (O) is approximately 16 g/mol.
- Therefore, the molar mass of water is calculated as follows:
\[ \text{Molar mass of water} = (2 \times 1) + (1 \times 16) = 2 + 16 = 18 \text{ g/mol} \]

### Step 2: Calculate the number of moles in 1.0 gram of water.
- The formula to calculate the number of moles is:
\[ \text{Moles} = \frac{\text{Given weight (g)}}{\text{Molar mass (g/mol)}} \]
- Substituting the values:
\[ \text{Moles} = \frac{1.0 \text{ g}}{18 \text{ g/mol}} \approx 0.05556 \text{ moles} \]

### Step 3: Convert moles to millimoles.
- To convert moles to millimoles, we multiply by 1000 (since 1 mole = 1000 millimoles):
\[ \text{Millimoles} = \text{Moles} \times 1000 \]
- Substituting the value:
\[ \text{Millimoles} = 0.05556 \text{ moles} \times 1000 \approx 55.56 \text{ millimoles} \]

### Final Answer:
The number of millimoles in 1.0 gram of water is approximately **55.56 millimoles**.

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