In the reaction h2 + n2 > 2 nh3, what coefficient should be placed in front of h2 to balance the reaction? a. 1 b. 2 c. 3 d. no coefficient is needed.

Long term exposure to waves can cause sunburns and skin cancer. a) visible b) infrared c) gamma rays d) ultraviole

What is the mass of 4 molecules of co2

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.