2. Atoms & Elements

If two atoms have the same number of protons in their nucleus, you can conclude for sure that they:

How many protons are present in a neutral atom of sodium (Na)?

Why is it accurate to say that an atom is mostly composed of empty space?

Which of the following best explains what makes a hydrogen atom different from a helium atom?

Which of the following best describes the electric charge of a neutron?

How many protons does a xenon atom have?

Which statement best explains why the atomic nucleus has a positive charge?

Which of the following best describes the approximate chemical composition by mass with which all stars are born?

Which particles are found in the nucleus of an argon atom?

How many neutrons are present in a neutral atom of phosphorus-31?

Which feature was included in Thomson's model of the atom that was not present in Dalton's model?

How many electrons are in the nucleus of an atom with an atomic number of 20?

Which statement is true of the atom shown in the diagram, which has 6 protons, 6 neutrons, and 6 electrons?

Which of the following combinations of atoms makes up a molecule of water?

All phosphorus atoms have the same: