Valence Electrons and Atomic Structure

The video tutorial explains Bohr models and their use in visualizing electron arrangements in atoms. It uses magnesium and chlorine as examples to illustrate the concept of electron shells, valence electrons, and ion formation. Magnesium, with 12 protons and 12 electrons, forms a stable ion by losing two electrons. Chlorine, with 17 protons and 17 electrons, gains an electron to form a stable chloride ion. The tutorial highlights the role of valence electrons in determining the chemical properties and stability of elements.

What is the primary purpose of Bohr models?

• To determine the atomic mass of elements

• To visualize the arrangement of electrons in an atom

• To predict the color of an element

• To calculate the number of protons in an atom

How many electrons does a neutral magnesium atom have?

• 16

• 12

• 10

• 14

What happens to magnesium when it loses its two valence electrons?

• It remains neutral

• It becomes a positive ion

• It becomes a negative ion

• It gains two more electrons

What are valence electrons responsible for?

• Determining the number of protons

• Determining the color of an element

• Determining the physical and chemical properties of an element

• Determining the atomic mass

How many valence electrons does chlorine have in its neutral state?

• 8

• 7

• 6

• 5

What change occurs when chlorine becomes a chloride ion?

• It loses an electron

• It gains an electron

• It gains a proton

• It loses a proton

What is the charge of a magnesium ion after losing two electrons?

• 1-

• 2-

• 1+

• 2+

How many electrons does a chloride ion have?

• 19

• 16

• 18

• 17

What remains unchanged when an atom becomes an ion?

• Number of protons

• Number of valence electrons

• Number of electrons

• Number of shells

What is the atomic mass of chlorine rounded to the nearest whole number?

• 36

• 35

• 34

• 37