Areas per million (ppm) denotes the quantity of models of a material contained in one million models of One more compound. It's a ratio expressing the concentration of 1 material within A different and it is widely accustomed to evaluate the purity of water, air, foodstuff products, and much more. https://online-ppm-calculator87395.blogozz.com/35769843/online-ppm-calculator-fundamentals-explained