Pieces for every million (ppm) denotes the amount of units of a material contained in 1,000,000 models of One more compound. It is a ratio expressing the concentration of 1 material within Yet another and is particularly widely used to evaluate the purity of water, air, foods solutions, plus more. https://cristianmbmvd.dm-blog.com/36706985/5-essential-elements-for-ppm-calculator