Equal weights of Hg and iodine are allowed to react completely to form a mixture of mercurous iodide and mercuric iodide. Calculate the ration of the masses of mercurous and mercuric iodides formed (Hg=201.I=117)

Answer

To solve the problem of finding the ratio of the masses of mercurous iodide (Hg2I2) and mercuric iodide (HgI2) formed when equal weights of mercury (Hg) and iodine (I2) react, we can follow these steps:

### Step 1: Determine the molar masses
- Molar mass of Hg = 201 g/mol
- Molar mass of I2 = 2 × 117 g/mol = 234 g/mol

### Step 2: Assume equal weights
Let’s assume we take 201 g of Hg and 234 g of I2 for the reaction.

### Step 3: Write the balanced chemical equations
1. For mercurous iodide (Hg2I2):
\[ 2 \text{Hg} + \text{I}_2 \rightarrow \text{Hg}_2\text{I}_2 \]
From this equation, 2 moles of Hg react with 1 mole of I2 to produce 1 mole of Hg2I2.

2. For mercuric iodide (HgI2):
\[ \text{Hg} + \text{I}_2 \rightarrow \text{HgI}_2 \]
Here, 1 mole of Hg reacts with 1 mole of I2 to produce 1 mole of HgI2.

### Step 4: Calculate the moles of reactants
- Moles of Hg = \(\frac{201 \text{ g}}{201 \text{ g/mol}} = 1 \text{ mol}\)
- Moles of I2 = \(\frac{234 \text{ g}}{234 \text{ g/mol}} = 1 \text{ mol}\)

### Step 5: Determine the limiting reactant
From the equations:
- To form 1 mole of Hg2I2, we need 2 moles of Hg and 1 mole of I2. Since we only have 1 mole of Hg, we cannot form Hg2I2.
- To form HgI2, we can use 1 mole of Hg and 1 mole of I2.

### Step 6: Calculate the products formed
Since we can only form HgI2:
- Moles of HgI2 formed = 1 mole (using 1 mole of Hg and 1 mole of I2).

### Step 7: Calculate the mass of HgI2 formed
- Molar mass of HgI2 = 201 g/mol (Hg) + 234 g/mol (I2) = 435 g/mol.
- Mass of HgI2 formed = 1 mole × 435 g/mol = 435 g.

### Step 8: Calculate the mass of mercurous iodide formed
Since we cannot form any Hg2I2 due to the limitation of Hg, the mass of mercurous iodide formed is 0 g.

### Step 9: Calculate the ratio of masses
The ratio of the masses of mercurous iodide (Hg2I2) to mercuric iodide (HgI2) is:
\[ \text{Ratio} = \frac{\text{mass of Hg2I2}}{\text{mass of HgI2}} = \frac{0 \text{ g}}{435 \text{ g}} = 0 \]

### Final Answer
The ratio of the masses of mercurous iodide to mercuric iodide formed is 0:435 or simply 0.