Understanding Mass Numbers, Atomic Numbers, Isotopes, and Counting Particles in Atoms

The video tutorial explains the structure of atoms, focusing on protons, neutrons, and electrons. It describes how elements are defined by their atomic numbers and introduces isotopes, which are variations of elements with different numbers of neutrons. The concept of ionization is discussed, explaining how atoms can gain or lose electrons to become ions. The tutorial also covers how to calculate the number of protons, neutrons, and electrons in atoms and ions, using aluminium as an example.

What is the charge of an atom when the number of protons equals the number of electrons?

• Positive

• Negative

• Neutral

• Variable

Which number is used to define different elements?

• Neutron number

• Electron number

• Atomic number

• Mass number

What distinguishes isotopes of the same element?

• Different atomic numbers

• Different number of neutrons

• Different number of electrons

• Different number of protons

What happens to an atom when it loses an electron?

• It becomes negatively charged

• It becomes positively charged

• It remains neutral

• It becomes an isotope

How many protons does an aluminium ion with a charge of +3 have?

• 10

• 13

• 27

• 14

If an aluminium ion has a mass number of 27 and 13 protons, how many neutrons does it have?

• 13

• 10

• 27

• 14

What is the number of electrons in an aluminium ion with a charge of +3?

• 10

• 13

• 14

• 16