An element has two naturally occurring isotopes with atomic masses of 112.90 amu and 114.90 amu. The relative abundances of these elements are 4.29% and 95.71%, respectively. What is the average atomic mass of the element?

The pressure inside a hydrogen-filled container was 2.10 atm at 21 ? c. what would the pressure be if the container was heated to 92 ? c ?

Sulfuric acid (a component of acid rain) reacts with limestone (calcium carbonate) to produce calcium sulfate and carbon dioxide. this damages buildings and statues made of limestone. which solution of sulfuric acid will damage these structures more quickly? a. 0.001% b. 0.005% c. 0.010% d. 0.015%

What happened in 2012 and how does it illustrate the importance of understanding the sun and how it works?