Atomic Structure and Electron Configuration

The video explains atomic structure, focusing on the nucleus, protons, neutrons, and electrons. It details how electrons are arranged in shells around the nucleus, with specific capacities for each shell. The video introduces dot and cross diagrams to represent electronic configurations and provides examples using elements like lithium, carbon, and magnesium. It also discusses how the arrangement of electrons affects an element's reactivity and its position in the periodic table.

What is the central part of an atom called?

• Neutron

• Nucleus

• Proton

• Electron

In a neutral atom, the number of electrons is equal to the number of what?

• Neutrons

• Protons

• Nuclei

• Shells

How many electrons can the first energy level hold?

• Two

• Four

• Six

• Eight

What is the maximum number of electrons that can be held in the second shell?

• Eight

• Six

• Four

• Two

How is the electronic configuration of lithium written?

• Li 2,2

• Li 1,2

• Li 2,1

• Li 1,1

What is the electronic configuration of carbon?

• C 2,2

• C 2,4

• C 4,2

• C 4,4

Which element has the electronic configuration Mg 2,8,2?

• Magnesium

• Carbon

• Lithium

• Oxygen

What determines the reactivity of an element?

• Number of energy levels

• Number of electrons in the outer shell

• Number of neutrons

• Number of protons

What does the number of electrons in the outer shell indicate about an element?

• Its density

• Its mass number

• Its group number on the periodic table

• Its atomic number

Elements in the same group have similar what?

• Densities

• Mass numbers

• Atomic numbers

• Reactivities