1. What is PPM and μg/mL?

PPM (parts per million) and μg/mL (micrograms per milliliter) are both units of concentration. For dilute aqueous solutions with density of 1 g/mL, these units are numerically equivalent.

2. How Does the Conversion Work?

The conversion is straightforward:

This equality holds true because:

• 1 mL of water weighs approximately 1 g (for dilute solutions)
• 1 g = 1,000,000 μg
• Therefore, 1 μg/mL = 1 μg per 1,000,000 μg = 1 ppm

3. When is This Conversion Valid?

Conditions: This simple conversion applies only to dilute aqueous solutions where the density is approximately 1 g/mL. For concentrated solutions or solutions with significantly different densities, more complex conversions are needed.

4. Using the Calculator

Instructions: Simply enter the concentration in μg/mL and the calculator will provide the equivalent value in ppm. The calculator assumes standard conditions for dilute aqueous solutions.

5. Frequently Asked Questions (FAQ)

Q1: Is this conversion always 1:1?
A: No, only for dilute aqueous solutions where density ≈ 1 g/mL. For other solvents or concentrated solutions, the conversion factor differs.

Q2: What's the difference between ppm and μg/mL?
A: ppm is a ratio (parts per million), while μg/mL is mass per volume. They're numerically equal only under specific conditions.

Q3: When would I need this conversion?
A: Common in environmental science, chemistry, and pharmacology when comparing concentration units.

Q4: How accurate is this conversion?
A: For water at standard temperature and pressure, it's exact. Accuracy decreases with changing density.

Q5: What about mg/L to ppm?
A: Similarly, 1 mg/L = 1 ppm for dilute aqueous solutions since 1 mg = 1000 μg and 1 L = 1000 mL.