C. C and Pb; Carbon and Lead being in the same group.
The units of ppm means parts per million. Also, It is equivalent to milligrams per liter. It is one way of expressing concentration of a substance. It u<span>sually used to describe the concentration of something in water or soil. We calculate the mass of CaCO3 as follows:
Mass = 75 mg/L (.050 L) = <span>3.75 mg CaCO3</span></span>
First one because Common synthetic materials are nylon, acrylic, polyester, carbon fiber, rayon and spandex. Synthetic materials are made from chemicals and are usually based on polymers. They are stronger than natural and regenerated materials.
Answer:
Solids cant react to each other because they are the same room temperature