Atom Structure - How Atoms Differ

Multiple Choice

Who discovered that atoms of an element contain a unique positive charge in their nucleus?

• Dmitri Mendeleev

• Henry Moseley

• Marie Curie

• Ernest Rutherford

Multiple Choice

What determines the order of elements in the periodic table?

• Atomic mass

• Number of neutrons

• Atomic number

• Number of electrons

Multiple Select

Which of the following statements are true about atomic number?

• It equals the number of protons in an atom.

• It equals the number of electrons in a neutral atom.

• It determines the element's position in the periodic table.

• It is always greater than the atomic mass.

Multiple Choice

If an atom has 30 protons, what is its atomic number and how many electrons does it have (assuming it is neutral)?

• Atomic number 30, 30 electrons

• Atomic number 8, 8 electrons

• Atomic number 82, 82 electrons

• Atomic number 12, 12 electrons

Multiple Choice

Which subatomic particle has a relative mass of 1/1840 and a negative electric charge?

• Electron

• Proton

• Neutron

• Positron

Multiple Choice

Based on the diagrams, what is the main difference between Carbon-12, Carbon-13, and Carbon-14?

• The number of neutrons in the nucleus

• The number of protons in the nucleus

• The number of electrons in the atom

• The type of element

Multiple Select

What information do you need to determine the number of neutrons in an isotope? Select all that apply.

• Atomic number

• Mass number

• Number of electrons

• Number of protons

Multiple Choice

Which of the following best explains how the weighted average atomic mass of chlorine is calculated from its isotopes?

• By adding the atomic masses of all isotopes and dividing by the number of isotopes.

• By multiplying the atomic mass of each isotope by its percent abundance and summing the results.

• By taking the isotope with the highest abundance as the atomic mass.

• By averaging the percent abundances of the isotopes.