Average Atomic Mass and Isotopes

The mass number of an element that has 18 protons, 18 electrons, and 19 neutrons is

The atomic number of an element that has 9 protons, 9 electrons, and 20 neutrons is

If the number of electrons changes you make a(an)

How many neutrons does Uranium-239 have

Which statement about subatomic particles is true

Which of the following is unique for any given element

Which is true about Oxygen-17, and Oxygen-18

How many protons are present in phosphorus-31

Two isotopes of carbon are carbon-12 and carbon 14. These isotopes differ from each other by two protons

What is the charge of an atom that has lost one electron

What is the charge of an atom that has gained one electron

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.

What is the average mass of this element?