An element has two isotopes. One isotope has a percent abundance of 75.0% and a mass number of 25 amu. The second isotopes has a percent abundance of25.0% and a mass number of 28 amu. What is the average atomic mass of the element? A.27.3
B.26.5
C.258
D.25.8

If a hydrogen atom is neutral, it must also have  one electron. an oxygen atom (o) has an atomic number of eight (8). this means a neutral oxygen atom has eight protons and eight electrons. the element actium (ac) has an atomic number of 89, so it has 89 protons and 89 electrons in a neutral atom

1.75 is the weight of one medium egg

It can be classified based on its