Which of the following gases was NOT part of Earth’s original atmosphere?

1. explain hydrogen peroxide, h 2 o 2 properties and decomposition reaction. 2. describe how each of the following natural cycles plays a part in earth’s climate system. (a) the water cycle (b) the carbon cycle

What is the percent by mass of oxygen in fe2o3

What are the first two quantum numbers for the electrons located in subshell 4d? what are the first three quantum numbers for the electrons located in subshell 2s? how many electrons can be held in a sublevel l = 3? how many electrons can be held in the energy level n = 4? how many electrons in an atom can share the quantum numbers n = 4 and l = 3?