The number of iodine atoms present in `1 cm^3` of its 0.1 M solution is

Options

A. `12.04 xx10^(23)`
B. `6.02xx10^(22)`
C. `12.04 xx10^(19)`
D. `6.02xx10^(20)`

Answer

To find the number of iodine atoms present in 1 cm³ of a 0.1 M iodine solution, we can follow these steps:

### Step 1: Understand the concentration
The concentration of the solution is given as 0.1 M (molar), which means there are 0.1 moles of iodine (I₂) in 1 liter of solution.

### Step 2: Convert liters to cm³
1 liter is equivalent to 1000 cm³. Therefore, the concentration of 0.1 M means:
- In 1000 cm³ of solution, there are 0.1 moles of I₂.

### Step 3: Calculate the number of moles in 1 cm³
To find the number of moles in 1 cm³ of the solution, we can set up a proportion:
\[ \text{Moles in 1 cm³} = \frac{0.1 \text{ moles}}{1000 \text{ cm³}} = 0.1 \times 10^{-3} \text{ moles} = 1 \times 10^{-4} \text{ moles} \]

### Step 4: Convert moles to molecules
Using Avogadro's number, which is \(6.022 \times 10^{23}\) molecules per mole, we can find the number of molecules in \(1 \times 10^{-4}\) moles of I₂:
\[ \text{Number of molecules} = 1 \times 10^{-4} \text{ moles} \times 6.022 \times 10^{23} \text{ molecules/mole} \]
\[ = 6.022 \times 10^{19} \text{ molecules of I₂} \]

### Step 5: Calculate the number of iodine atoms
Each molecule of iodine (I₂) contains 2 iodine atoms. Therefore, to find the total number of iodine atoms, we multiply the number of molecules by 2:
\[ \text{Number of iodine atoms} = 6.022 \times 10^{19} \text{ molecules} \times 2 = 1.2044 \times 10^{20} \text{ atoms} \]

### Final Answer
The number of iodine atoms present in 1 cm³ of a 0.1 M iodine solution is approximately \(1.2044 \times 10^{20}\) atoms.

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