Problem 164 - A Complete Resource Book in Chemistry for JEE Main

Question

Which two of the following substances are used for preparing iodized salt? (a) KI (b) \(\mathrm{I}_{2}\) (c) \(\mathrm{HI}\) (d) \(\mathrm{KIO}_{3}\)

Step-by-Step Solution

Answer

KI and KIO3 are used to prepare iodized salt.

Step 1: Understanding the Question

To determine which substances are used to make iodized salt, we need to understand that iodized salt is regular salt with added iodine. The forms of iodine that are commonly used to fortify salt include potassium iodide (KI) and potassium iodate (KIO3).

Step 2: Identifying the Correct Answer from Options

From the given list ( (a) KI, (b) I2, (c) HI, (d) KIO3), the substances that correspond to the iodine forms used in iodized salt are KI (potassium iodide) and KIO3 (potassium iodate). These are the chemical compounds commonly used in the iodization process.

Key Concepts

Potassium Iodide (KI)

Potassium iodide, often abbreviated as KI, is a vital compound used in the nutritional fortification of salt. This chemical is an iodine source that aids in preventing iodine deficiency in populations. Iodine is an essential mineral crucial for the production of thyroid hormones, which are important for metabolic processes in the human body.
This white crystalline salt is highly soluble in water, making it easy to mix evenly with table salt.
KI is especially favored for its high bioavailability, meaning it is easily absorbed and utilized by the human body.
When iodized salt is consumed, potassium iodide provides a stable form of iodine. This ensures the thyroid gland has a continual supply to function properly, helping to prevent health issues such as goiter.
KI is not only used for iodization but also has applications in the medical field, such as in radiation shielding and expectorants.

Potassium Iodate (KIO3)

Potassium iodate (KIO3) is another compound extensively used in the preparation of iodized salt. Similar to potassium iodide, KIO3 also introduces iodine into the salt. However, it is more stable than KI, particularly in environments with high humidity or temperatures.

• It is commonly chosen for iodization in regions where shelf-life and stability are critical factors.
• KIO3 is less soluble in water compared to KI, which may influence the iodization process slightly.

Even so, once consumed, it efficiently delivers iodine to the body.
The body then converts KIO3 into iodide, which the thyroid gland uses to produce hormones.
This form of iodine fortification ensures communities at risk of iodine deficiency diseases get adequate nutrition.

Iodization Process

The iodization process is a public health intervention aimed at eliminating iodine deficiency disorders. This process involves the addition of iodine to table salt, which is a universally consumed product. The goal is simple: to ensure that populations receive adequate iodine through their diet.
During this process, either potassium iodide (KI) or potassium iodate (KIO3) is mixed with salt.

• This is done in the right proportions and under controlled conditions to ensure even distribution.
• The fortification is mild enough to not alter the taste or appearance of the salt.

This method is cost-effective and has been widely implemented globally.
It significantly reduces the risk of health problems associated with iodine deficiency, such as intellectual disabilities in children and goiter in adults.
The success of this process relies on careful regulation and consistent monitoring to maintain optimal iodine levels in the salt.