Iron is found in Earth's crust as several iron compounds. Calculate the mass in kilograms of the amount of each of the following iron compounds that contains 1.0×103kg of iron. Fe2O3 (hematite)

The big bang nucleosynthesis theory states that elements were produced in the first few minutes of the big bang while elements have their origins in the interiors of stars, forming much later in the history of the universe.

According to periodic trend, which of the following most likely has the highest ionization energy? kr be ni sc

Ahydrogen atom has 1 electron. how many bonds can hydrogen form? a) 1 b) 2 c) 3 d) 4 e) 5