Which element has both metallic and nonmetallic properties? * 1 point Rb Rn Si Sr

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.

Which of the following units is not an official si unit? mole liter kilogram ampere

What is the ph of a solution that has a hydrogen ion concentration of 1.0 * 10 -9 m?