There are only two isotopes in made-up element "Z". The first isotope has a mass of 79 amu and the second isotope has a mass of 86 amu. If each isotope comprises half of the total elemental abundance, what is the atomic mass of the element?

Nitrogen (n), phosphorus (p), and potassium (k) are the main nutrients in plant fertilizers. according to an industry convention, the numbers on the label refer to the mass percents of n, p2o5, and k2o, in that order. calculate the n: p: k ratio of a 30: 10: 10 fertilizer in terms of moles of each element, and express it as x: y: 1.0.

How many moles of al3+ ions are in 1.25 moles of al2o3

How does the presence of oxygen affect the chemical pathways used to extract energy from glucose?