What is the percentage by weight of 5000 ppm?

To convert parts per million (ppm) to a percentage by weight, you can use the relationship that 1 ppm is equivalent to 0.0001% by weight. Therefore, to find out what percentage 5000 ppm represents, you can perform the following calculation:

First, you recognize that 5000 ppm means there are 5000 parts of a substance in one million parts of the total mixture. The conversion to percentage by weight can be calculated as follows:

1. Divide the number of ppm (5000) by 10,000 (since 1% is equivalent to 10,000 ppm).
2. The calculation is: 5000 / 1000000 = 0.005.
3. To convert this to a percentage, you multiply by 100, which gives you 0.5% by weight.

This shows that 5000 ppm directly translates to 0.5% by weight, confirming that the correct answer is indeed 0.5% by weight. This understanding is essential when assessing lead levels as it enables accurate measurement and assessment of lead exposure risks in various environments.