Which of the following Noble Gases has a mass of 10.0 g?

Hydrogenation reactions, in which h2 and an "unsaturated" organic compound combine, are used in the food, fuel, and polymer industries. in the simplest case, ethene (c2h4) and h2 form ethane (c2h6). if 140 kj is given off per mole of c2h4 reacting, how much heat (in mj) is released when 12 kg of c2h6 forms?

Describe the forces both attractive and repulsive that occur as two atoms move closer together.

What are fossils of organisms that existed over a wide area but only for a limited time period called?