For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have?

An uncharged atom has six electrons. the nucleus of this atom must contain _______ protons.

Rounded to the nearest whole number, how many protons are in an atom of Krypton? 36 48 84 120

How many protons, neutrons, and electrons are there in a neutral atom of ³⁰P (phosphorus-30)?

An uncharged atom has six electrons. The nucleus of this atom must contain _______ protons.

If an atom contains 3 protons, 4 neutrons, and 3 electrons, its mass number is

All atoms of an element have the same number of ________.

What is the atomic mass number of carbon-13 (6 protons, 7 neutrons, 6 electrons)?

What is the mass number for an atom of barium containing 56 protons and 82 neutrons?