An oxide of iodine (I = 127) contains 25.4 g for 8 g of oxygen. Its formula will be:

• (a) - I₂O₃
• (b) - I₂O
• (c) - I₂O₅
• (d) - I₂O₇

To determine the formula of the iodine oxide, we first need to find the number of moles of iodine and oxygen in the compound.

Calculating Moles of Oxygen

The molar mass of oxygen (O) is approximately 16 g/mol. Given that there are 8 g of oxygen:

• Moles of O = 8 g / 16 g/mol = 0.5 moles

Calculating Moles of Iodine

The molar mass of iodine (I) is 127 g/mol. With 25.4 g of iodine:

• Moles of I = 25.4 g / 127 g/mol ≈ 0.2 moles

Finding the Ratio

Next, we find the simplest whole number ratio of iodine to oxygen:

• Ratio of I to O = 0.2 moles I : 0.5 moles O
• To simplify, divide both by 0.2: 1 I : 2.5 O
• Multiplying by 2 gives us 2 I : 5 O

Determining the Chemical Formula

The ratio of iodine to oxygen suggests the formula is I₂O₅. Therefore, the correct answer is: