Horrok’s apparatus determines Chloride which has to have a holding level of –
**Core Concept**
Horrock's apparatus is a device used to determine chloride levels in sweat or other bodily fluids. The principle behind this apparatus is the measurement of chloride ions in the sample, which is essential for diagnosing and managing various conditions, including cystic fibrosis.
**Why the Correct Answer is Right**
The correct answer is based on the principle of chloride ion measurement in the Horrock's apparatus. Chloride ions are a critical component of electrolyte balance in the body, and their levels can affect various bodily functions. In the Horrock's apparatus, chloride ions are measured using a specific reaction that involves the use of silver nitrate (AgNO3). The reaction is as follows: AgNO3 + Cl- → AgCl + NO3-. The holding level of chloride ions in the apparatus is critical for accurate measurement.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify the correct holding level of chloride ions in the Horrock's apparatus.
* **Option B:** This option is incorrect because it is not the recommended holding level for chloride ions in the Horrock's apparatus.
* **Option C:** This option is incorrect because it does not accurately reflect the optimal holding level of chloride ions in the Horrock's apparatus.
**Clinical Pearl / High-Yield Fact**
A key point to remember when using the Horrock's apparatus is that the holding level of chloride ions must be maintained within a specific range to ensure accurate measurements. This is crucial for diagnosing and managing conditions such as cystic fibrosis, where chloride ion levels can be abnormal.
**Correct Answer:** 150 mmol/L.